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stack.c revision 1.3
      1 /* Print and select stack frames for GDB, the GNU debugger.
      2 
      3    Copyright (C) 1986-2015 Free Software Foundation, Inc.
      4 
      5    This file is part of GDB.
      6 
      7    This program is free software; you can redistribute it and/or modify
      8    it under the terms of the GNU General Public License as published by
      9    the Free Software Foundation; either version 3 of the License, or
     10    (at your option) any later version.
     11 
     12    This program is distributed in the hope that it will be useful,
     13    but WITHOUT ANY WARRANTY; without even the implied warranty of
     14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     15    GNU General Public License for more details.
     16 
     17    You should have received a copy of the GNU General Public License
     18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
     19 
     20 #include "defs.h"
     21 #include "value.h"
     22 #include "symtab.h"
     23 #include "gdbtypes.h"
     24 #include "expression.h"
     25 #include "language.h"
     26 #include "frame.h"
     27 #include "gdbcmd.h"
     28 #include "gdbcore.h"
     29 #include "target.h"
     30 #include "source.h"
     31 #include "breakpoint.h"
     32 #include "demangle.h"
     33 #include "inferior.h"
     34 #include "annotate.h"
     35 #include "ui-out.h"
     36 #include "block.h"
     37 #include "stack.h"
     38 #include "dictionary.h"
     39 #include "reggroups.h"
     40 #include "regcache.h"
     41 #include "solib.h"
     42 #include "valprint.h"
     43 #include "gdbthread.h"
     44 #include "cp-support.h"
     45 #include "disasm.h"
     46 #include "inline-frame.h"
     47 #include "linespec.h"
     48 #include "cli/cli-utils.h"
     49 #include "objfiles.h"
     50 
     51 #include <ctype.h>
     52 #include "symfile.h"
     53 #include "extension.h"
     54 
     55 void (*deprecated_selected_frame_level_changed_hook) (int);
     56 
     57 /* The possible choices of "set print frame-arguments", and the value
     58    of this setting.  */
     59 
     60 static const char *const print_frame_arguments_choices[] =
     61   {"all", "scalars", "none", NULL};
     62 static const char *print_frame_arguments = "scalars";
     63 
     64 /* If non-zero, don't invoke pretty-printers for frame arguments.  */
     65 static int print_raw_frame_arguments;
     66 
     67 /* The possible choices of "set print entry-values", and the value
     68    of this setting.  */
     69 
     70 const char print_entry_values_no[] = "no";
     71 const char print_entry_values_only[] = "only";
     72 const char print_entry_values_preferred[] = "preferred";
     73 const char print_entry_values_if_needed[] = "if-needed";
     74 const char print_entry_values_both[] = "both";
     75 const char print_entry_values_compact[] = "compact";
     76 const char print_entry_values_default[] = "default";
     77 static const char *const print_entry_values_choices[] =
     78 {
     79   print_entry_values_no,
     80   print_entry_values_only,
     81   print_entry_values_preferred,
     82   print_entry_values_if_needed,
     83   print_entry_values_both,
     84   print_entry_values_compact,
     85   print_entry_values_default,
     86   NULL
     87 };
     88 const char *print_entry_values = print_entry_values_default;
     89 
     90 /* Prototypes for local functions.  */
     91 
     92 static void print_frame_local_vars (struct frame_info *, int,
     93 				    struct ui_file *);
     94 
     95 static void print_frame (struct frame_info *frame, int print_level,
     96 			 enum print_what print_what,  int print_args,
     97 			 struct symtab_and_line sal);
     98 
     99 static void set_last_displayed_sal (int valid,
    100 				    struct program_space *pspace,
    101 				    CORE_ADDR addr,
    102 				    struct symtab *symtab,
    103 				    int line);
    104 
    105 /* Zero means do things normally; we are interacting directly with the
    106    user.  One means print the full filename and linenumber when a
    107    frame is printed, and do so in a format emacs18/emacs19.22 can
    108    parse.  Two means print similar annotations, but in many more
    109    cases and in a slightly different syntax.  */
    110 
    111 int annotation_level = 0;
    112 
    113 /* These variables hold the last symtab and line we displayed to the user.
    114  * This is where we insert a breakpoint or a skiplist entry by default.  */
    115 static int last_displayed_sal_valid = 0;
    116 static struct program_space *last_displayed_pspace = 0;
    117 static CORE_ADDR last_displayed_addr = 0;
    118 static struct symtab *last_displayed_symtab = 0;
    119 static int last_displayed_line = 0;
    120 
    121 
    123 /* Return 1 if we should display the address in addition to the location,
    124    because we are in the middle of a statement.  */
    125 
    126 static int
    127 frame_show_address (struct frame_info *frame,
    128 		    struct symtab_and_line sal)
    129 {
    130   /* If there is a line number, but no PC, then there is no location
    131      information associated with this sal.  The only way that should
    132      happen is for the call sites of inlined functions (SAL comes from
    133      find_frame_sal).  Otherwise, we would have some PC range if the
    134      SAL came from a line table.  */
    135   if (sal.line != 0 && sal.pc == 0 && sal.end == 0)
    136     {
    137       if (get_next_frame (frame) == NULL)
    138 	gdb_assert (inline_skipped_frames (inferior_ptid) > 0);
    139       else
    140 	gdb_assert (get_frame_type (get_next_frame (frame)) == INLINE_FRAME);
    141       return 0;
    142     }
    143 
    144   return get_frame_pc (frame) != sal.pc;
    145 }
    146 
    147 /* Show or print a stack frame FRAME briefly.  The output is format
    148    according to PRINT_LEVEL and PRINT_WHAT printing the frame's
    149    relative level, function name, argument list, and file name and
    150    line number.  If the frame's PC is not at the beginning of the
    151    source line, the actual PC is printed at the beginning.  */
    152 
    153 void
    154 print_stack_frame (struct frame_info *frame, int print_level,
    155 		   enum print_what print_what,
    156 		   int set_current_sal)
    157 {
    158   volatile struct gdb_exception e;
    159 
    160   /* For mi, alway print location and address.  */
    161   if (ui_out_is_mi_like_p (current_uiout))
    162     print_what = LOC_AND_ADDRESS;
    163 
    164   TRY_CATCH (e, RETURN_MASK_ERROR)
    165     {
    166       print_frame_info (frame, print_level, print_what, 1 /* print_args */,
    167 			set_current_sal);
    168       if (set_current_sal)
    169 	set_current_sal_from_frame (frame);
    170     }
    171 }
    172 
    173 /* Print nameless arguments of frame FRAME on STREAM, where START is
    174    the offset of the first nameless argument, and NUM is the number of
    175    nameless arguments to print.  FIRST is nonzero if this is the first
    176    argument (not just the first nameless argument).  */
    177 
    178 static void
    179 print_frame_nameless_args (struct frame_info *frame, long start, int num,
    180 			   int first, struct ui_file *stream)
    181 {
    182   struct gdbarch *gdbarch = get_frame_arch (frame);
    183   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
    184   int i;
    185   CORE_ADDR argsaddr;
    186   long arg_value;
    187 
    188   for (i = 0; i < num; i++)
    189     {
    190       QUIT;
    191       argsaddr = get_frame_args_address (frame);
    192       if (!argsaddr)
    193 	return;
    194       arg_value = read_memory_integer (argsaddr + start,
    195 				       sizeof (int), byte_order);
    196       if (!first)
    197 	fprintf_filtered (stream, ", ");
    198       fprintf_filtered (stream, "%ld", arg_value);
    199       first = 0;
    200       start += sizeof (int);
    201     }
    202 }
    203 
    204 /* Print single argument of inferior function.  ARG must be already
    205    read in.
    206 
    207    Errors are printed as if they would be the parameter value.  Use zeroed ARG
    208    iff it should not be printed accoring to user settings.  */
    209 
    210 static void
    211 print_frame_arg (const struct frame_arg *arg)
    212 {
    213   struct ui_out *uiout = current_uiout;
    214   volatile struct gdb_exception except;
    215   struct cleanup *old_chain;
    216   struct ui_file *stb;
    217 
    218   stb = mem_fileopen ();
    219   old_chain = make_cleanup_ui_file_delete (stb);
    220 
    221   gdb_assert (!arg->val || !arg->error);
    222   gdb_assert (arg->entry_kind == print_entry_values_no
    223 	      || arg->entry_kind == print_entry_values_only
    224 	      || (!ui_out_is_mi_like_p (uiout)
    225 		  && arg->entry_kind == print_entry_values_compact));
    226 
    227   annotate_arg_begin ();
    228 
    229   make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
    230   fprintf_symbol_filtered (stb, SYMBOL_PRINT_NAME (arg->sym),
    231 			   SYMBOL_LANGUAGE (arg->sym), DMGL_PARAMS | DMGL_ANSI);
    232   if (arg->entry_kind == print_entry_values_compact)
    233     {
    234       /* It is OK to provide invalid MI-like stream as with
    235 	 PRINT_ENTRY_VALUE_COMPACT we never use MI.  */
    236       fputs_filtered ("=", stb);
    237 
    238       fprintf_symbol_filtered (stb, SYMBOL_PRINT_NAME (arg->sym),
    239 			       SYMBOL_LANGUAGE (arg->sym),
    240 			       DMGL_PARAMS | DMGL_ANSI);
    241     }
    242   if (arg->entry_kind == print_entry_values_only
    243       || arg->entry_kind == print_entry_values_compact)
    244     fputs_filtered ("@entry", stb);
    245   ui_out_field_stream (uiout, "name", stb);
    246   annotate_arg_name_end ();
    247   ui_out_text (uiout, "=");
    248 
    249   if (!arg->val && !arg->error)
    250     ui_out_text (uiout, "...");
    251   else
    252     {
    253       if (arg->error)
    254 	except.message = arg->error;
    255       else
    256 	{
    257 	  /* TRY_CATCH has two statements, wrap it in a block.  */
    258 
    259 	  TRY_CATCH (except, RETURN_MASK_ERROR)
    260 	    {
    261 	      const struct language_defn *language;
    262 	      struct value_print_options opts;
    263 
    264 	      /* Avoid value_print because it will deref ref parameters.  We
    265 		 just want to print their addresses.  Print ??? for args whose
    266 		 address we do not know.  We pass 2 as "recurse" to val_print
    267 		 because our standard indentation here is 4 spaces, and
    268 		 val_print indents 2 for each recurse.  */
    269 
    270 	      annotate_arg_value (value_type (arg->val));
    271 
    272 	      /* Use the appropriate language to display our symbol, unless the
    273 		 user forced the language to a specific language.  */
    274 	      if (language_mode == language_mode_auto)
    275 		language = language_def (SYMBOL_LANGUAGE (arg->sym));
    276 	      else
    277 		language = current_language;
    278 
    279 	      get_no_prettyformat_print_options (&opts);
    280 	      opts.deref_ref = 1;
    281 	      opts.raw = print_raw_frame_arguments;
    282 
    283 	      /* True in "summary" mode, false otherwise.  */
    284 	      opts.summary = !strcmp (print_frame_arguments, "scalars");
    285 
    286 	      common_val_print (arg->val, stb, 2, &opts, language);
    287 	    }
    288 	}
    289       if (except.message)
    290 	fprintf_filtered (stb, _("<error reading variable: %s>"),
    291 			  except.message);
    292     }
    293 
    294   ui_out_field_stream (uiout, "value", stb);
    295 
    296   /* Also invoke ui_out_tuple_end.  */
    297   do_cleanups (old_chain);
    298 
    299   annotate_arg_end ();
    300 }
    301 
    302 /* Read in inferior function local SYM at FRAME into ARGP.  Caller is
    303    responsible for xfree of ARGP->ERROR.  This function never throws an
    304    exception.  */
    305 
    306 void
    307 read_frame_local (struct symbol *sym, struct frame_info *frame,
    308 		  struct frame_arg *argp)
    309 {
    310   volatile struct gdb_exception except;
    311   struct value *val = NULL;
    312 
    313   TRY_CATCH (except, RETURN_MASK_ERROR)
    314     {
    315       val = read_var_value (sym, frame);
    316     }
    317 
    318   argp->error = (val == NULL) ? xstrdup (except.message) : NULL;
    319   argp->sym = sym;
    320   argp->val = val;
    321 }
    322 
    323 /* Read in inferior function parameter SYM at FRAME into ARGP.  Caller is
    324    responsible for xfree of ARGP->ERROR.  This function never throws an
    325    exception.  */
    326 
    327 void
    328 read_frame_arg (struct symbol *sym, struct frame_info *frame,
    329 	        struct frame_arg *argp, struct frame_arg *entryargp)
    330 {
    331   struct value *val = NULL, *entryval = NULL;
    332   char *val_error = NULL, *entryval_error = NULL;
    333   int val_equal = 0;
    334   volatile struct gdb_exception except;
    335 
    336   if (print_entry_values != print_entry_values_only
    337       && print_entry_values != print_entry_values_preferred)
    338     {
    339       TRY_CATCH (except, RETURN_MASK_ERROR)
    340 	{
    341 	  val = read_var_value (sym, frame);
    342 	}
    343       if (!val)
    344 	{
    345 	  val_error = alloca (strlen (except.message) + 1);
    346 	  strcpy (val_error, except.message);
    347 	}
    348     }
    349 
    350   if (SYMBOL_COMPUTED_OPS (sym) != NULL
    351       && SYMBOL_COMPUTED_OPS (sym)->read_variable_at_entry != NULL
    352       && print_entry_values != print_entry_values_no
    353       && (print_entry_values != print_entry_values_if_needed
    354 	  || !val || value_optimized_out (val)))
    355     {
    356       TRY_CATCH (except, RETURN_MASK_ERROR)
    357 	{
    358 	  const struct symbol_computed_ops *ops;
    359 
    360 	  ops = SYMBOL_COMPUTED_OPS (sym);
    361 	  entryval = ops->read_variable_at_entry (sym, frame);
    362 	}
    363       if (!entryval)
    364 	{
    365 	  entryval_error = alloca (strlen (except.message) + 1);
    366 	  strcpy (entryval_error, except.message);
    367 	}
    368 
    369       if (except.error == NO_ENTRY_VALUE_ERROR
    370 	  || (entryval && value_optimized_out (entryval)))
    371 	{
    372 	  entryval = NULL;
    373 	  entryval_error = NULL;
    374 	}
    375 
    376       if (print_entry_values == print_entry_values_compact
    377 	  || print_entry_values == print_entry_values_default)
    378 	{
    379 	  /* For MI do not try to use print_entry_values_compact for ARGP.  */
    380 
    381 	  if (val && entryval && !ui_out_is_mi_like_p (current_uiout))
    382 	    {
    383 	      struct type *type = value_type (val);
    384 
    385 	      if (value_lazy (val))
    386 		value_fetch_lazy (val);
    387 	      if (value_lazy (entryval))
    388 		value_fetch_lazy (entryval);
    389 
    390 	      if (value_contents_eq (val, 0, entryval, 0, TYPE_LENGTH (type)))
    391 		{
    392 		  /* Initialize it just to avoid a GCC false warning.  */
    393 		  struct value *val_deref = NULL, *entryval_deref;
    394 
    395 		  /* DW_AT_GNU_call_site_value does match with the current
    396 		     value.  If it is a reference still try to verify if
    397 		     dereferenced DW_AT_GNU_call_site_data_value does not
    398 		     differ.  */
    399 
    400 		  TRY_CATCH (except, RETURN_MASK_ERROR)
    401 		    {
    402 		      struct type *type_deref;
    403 
    404 		      val_deref = coerce_ref (val);
    405 		      if (value_lazy (val_deref))
    406 			value_fetch_lazy (val_deref);
    407 		      type_deref = value_type (val_deref);
    408 
    409 		      entryval_deref = coerce_ref (entryval);
    410 		      if (value_lazy (entryval_deref))
    411 			value_fetch_lazy (entryval_deref);
    412 
    413 		      /* If the reference addresses match but dereferenced
    414 			 content does not match print them.  */
    415 		      if (val != val_deref
    416 			  && value_contents_eq (val_deref, 0,
    417 						entryval_deref, 0,
    418 						TYPE_LENGTH (type_deref)))
    419 			val_equal = 1;
    420 		    }
    421 
    422 		  /* Value was not a reference; and its content matches.  */
    423 		  if (val == val_deref)
    424 		    val_equal = 1;
    425 		  /* If the dereferenced content could not be fetched do not
    426 		     display anything.  */
    427 		  else if (except.error == NO_ENTRY_VALUE_ERROR)
    428 		    val_equal = 1;
    429 		  else if (except.message)
    430 		    {
    431 		      entryval_error = alloca (strlen (except.message) + 1);
    432 		      strcpy (entryval_error, except.message);
    433 		    }
    434 
    435 		  if (val_equal)
    436 		    entryval = NULL;
    437 		}
    438 	    }
    439 
    440 	  /* Try to remove possibly duplicate error message for ENTRYARGP even
    441 	     in MI mode.  */
    442 
    443 	  if (val_error && entryval_error
    444 	      && strcmp (val_error, entryval_error) == 0)
    445 	    {
    446 	      entryval_error = NULL;
    447 
    448 	      /* Do not se VAL_EQUAL as the same error message may be shown for
    449 		 the entry value even if no entry values are present in the
    450 		 inferior.  */
    451 	    }
    452 	}
    453     }
    454 
    455   if (entryval == NULL)
    456     {
    457       if (print_entry_values == print_entry_values_preferred)
    458 	{
    459 	  TRY_CATCH (except, RETURN_MASK_ERROR)
    460 	    {
    461 	      val = read_var_value (sym, frame);
    462 	    }
    463 	  if (!val)
    464 	    {
    465 	      val_error = alloca (strlen (except.message) + 1);
    466 	      strcpy (val_error, except.message);
    467 	    }
    468 	}
    469       if (print_entry_values == print_entry_values_only
    470 	  || print_entry_values == print_entry_values_both
    471 	  || (print_entry_values == print_entry_values_preferred
    472 	      && (!val || value_optimized_out (val))))
    473 	{
    474 	  entryval = allocate_optimized_out_value (SYMBOL_TYPE (sym));
    475 	  entryval_error = NULL;
    476 	}
    477     }
    478   if ((print_entry_values == print_entry_values_compact
    479        || print_entry_values == print_entry_values_if_needed
    480        || print_entry_values == print_entry_values_preferred)
    481       && (!val || value_optimized_out (val)) && entryval != NULL)
    482     {
    483       val = NULL;
    484       val_error = NULL;
    485     }
    486 
    487   argp->sym = sym;
    488   argp->val = val;
    489   argp->error = val_error ? xstrdup (val_error) : NULL;
    490   if (!val && !val_error)
    491     argp->entry_kind = print_entry_values_only;
    492   else if ((print_entry_values == print_entry_values_compact
    493 	   || print_entry_values == print_entry_values_default) && val_equal)
    494     {
    495       argp->entry_kind = print_entry_values_compact;
    496       gdb_assert (!ui_out_is_mi_like_p (current_uiout));
    497     }
    498   else
    499     argp->entry_kind = print_entry_values_no;
    500 
    501   entryargp->sym = sym;
    502   entryargp->val = entryval;
    503   entryargp->error = entryval_error ? xstrdup (entryval_error) : NULL;
    504   if (!entryval && !entryval_error)
    505     entryargp->entry_kind = print_entry_values_no;
    506   else
    507     entryargp->entry_kind = print_entry_values_only;
    508 }
    509 
    510 /* Print the arguments of frame FRAME on STREAM, given the function
    511    FUNC running in that frame (as a symbol), where NUM is the number
    512    of arguments according to the stack frame (or -1 if the number of
    513    arguments is unknown).  */
    514 
    515 /* Note that currently the "number of arguments according to the
    516    stack frame" is only known on VAX where i refers to the "number of
    517    ints of arguments according to the stack frame".  */
    518 
    519 static void
    520 print_frame_args (struct symbol *func, struct frame_info *frame,
    521 		  int num, struct ui_file *stream)
    522 {
    523   struct ui_out *uiout = current_uiout;
    524   int first = 1;
    525   /* Offset of next stack argument beyond the one we have seen that is
    526      at the highest offset, or -1 if we haven't come to a stack
    527      argument yet.  */
    528   long highest_offset = -1;
    529   /* Number of ints of arguments that we have printed so far.  */
    530   int args_printed = 0;
    531   struct cleanup *old_chain;
    532   struct ui_file *stb;
    533   /* True if we should print arguments, false otherwise.  */
    534   int print_args = strcmp (print_frame_arguments, "none");
    535 
    536   stb = mem_fileopen ();
    537   old_chain = make_cleanup_ui_file_delete (stb);
    538 
    539   if (func)
    540     {
    541       const struct block *b = SYMBOL_BLOCK_VALUE (func);
    542       struct block_iterator iter;
    543       struct symbol *sym;
    544 
    545       ALL_BLOCK_SYMBOLS (b, iter, sym)
    546         {
    547 	  struct frame_arg arg, entryarg;
    548 
    549 	  QUIT;
    550 
    551 	  /* Keep track of the highest stack argument offset seen, and
    552 	     skip over any kinds of symbols we don't care about.  */
    553 
    554 	  if (!SYMBOL_IS_ARGUMENT (sym))
    555 	    continue;
    556 
    557 	  switch (SYMBOL_CLASS (sym))
    558 	    {
    559 	    case LOC_ARG:
    560 	    case LOC_REF_ARG:
    561 	      {
    562 		long current_offset = SYMBOL_VALUE (sym);
    563 		int arg_size = TYPE_LENGTH (SYMBOL_TYPE (sym));
    564 
    565 		/* Compute address of next argument by adding the size of
    566 		   this argument and rounding to an int boundary.  */
    567 		current_offset =
    568 		  ((current_offset + arg_size + sizeof (int) - 1)
    569 		   & ~(sizeof (int) - 1));
    570 
    571 		/* If this is the highest offset seen yet, set
    572 		   highest_offset.  */
    573 		if (highest_offset == -1
    574 		    || (current_offset > highest_offset))
    575 		  highest_offset = current_offset;
    576 
    577 		/* Add the number of ints we're about to print to
    578 		   args_printed.  */
    579 		args_printed += (arg_size + sizeof (int) - 1) / sizeof (int);
    580 	      }
    581 
    582 	      /* We care about types of symbols, but don't need to
    583 		 keep track of stack offsets in them.  */
    584 	    case LOC_REGISTER:
    585 	    case LOC_REGPARM_ADDR:
    586 	    case LOC_COMPUTED:
    587 	    case LOC_OPTIMIZED_OUT:
    588 	    default:
    589 	      break;
    590 	    }
    591 
    592 	  /* We have to look up the symbol because arguments can have
    593 	     two entries (one a parameter, one a local) and the one we
    594 	     want is the local, which lookup_symbol will find for us.
    595 	     This includes gcc1 (not gcc2) on SPARC when passing a
    596 	     small structure and gcc2 when the argument type is float
    597 	     and it is passed as a double and converted to float by
    598 	     the prologue (in the latter case the type of the LOC_ARG
    599 	     symbol is double and the type of the LOC_LOCAL symbol is
    600 	     float).  */
    601 	  /* But if the parameter name is null, don't try it.  Null
    602 	     parameter names occur on the RS/6000, for traceback
    603 	     tables.  FIXME, should we even print them?  */
    604 
    605 	  if (*SYMBOL_LINKAGE_NAME (sym))
    606 	    {
    607 	      struct symbol *nsym;
    608 
    609 	      nsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym),
    610 				    b, VAR_DOMAIN, NULL);
    611 	      gdb_assert (nsym != NULL);
    612 	      if (SYMBOL_CLASS (nsym) == LOC_REGISTER
    613 		  && !SYMBOL_IS_ARGUMENT (nsym))
    614 		{
    615 		  /* There is a LOC_ARG/LOC_REGISTER pair.  This means
    616 		     that it was passed on the stack and loaded into a
    617 		     register, or passed in a register and stored in a
    618 		     stack slot.  GDB 3.x used the LOC_ARG; GDB
    619 		     4.0-4.11 used the LOC_REGISTER.
    620 
    621 		     Reasons for using the LOC_ARG:
    622 
    623 		     (1) Because find_saved_registers may be slow for
    624 		         remote debugging.
    625 
    626 		     (2) Because registers are often re-used and stack
    627 		         slots rarely (never?) are.  Therefore using
    628 		         the stack slot is much less likely to print
    629 		         garbage.
    630 
    631 		     Reasons why we might want to use the LOC_REGISTER:
    632 
    633 		     (1) So that the backtrace prints the same value
    634 		         as "print foo".  I see no compelling reason
    635 		         why this needs to be the case; having the
    636 		         backtrace print the value which was passed
    637 		         in, and "print foo" print the value as
    638 		         modified within the called function, makes
    639 		         perfect sense to me.
    640 
    641 		     Additional note: It might be nice if "info args"
    642 		     displayed both values.
    643 
    644 		     One more note: There is a case with SPARC
    645 		     structure passing where we need to use the
    646 		     LOC_REGISTER, but this is dealt with by creating
    647 		     a single LOC_REGPARM in symbol reading.  */
    648 
    649 		  /* Leave sym (the LOC_ARG) alone.  */
    650 		  ;
    651 		}
    652 	      else
    653 		sym = nsym;
    654 	    }
    655 
    656 	  /* Print the current arg.  */
    657 	  if (!first)
    658 	    ui_out_text (uiout, ", ");
    659 	  ui_out_wrap_hint (uiout, "    ");
    660 
    661 	  if (!print_args)
    662 	    {
    663 	      memset (&arg, 0, sizeof (arg));
    664 	      arg.sym = sym;
    665 	      arg.entry_kind = print_entry_values_no;
    666 	      memset (&entryarg, 0, sizeof (entryarg));
    667 	      entryarg.sym = sym;
    668 	      entryarg.entry_kind = print_entry_values_no;
    669 	    }
    670 	  else
    671 	    read_frame_arg (sym, frame, &arg, &entryarg);
    672 
    673 	  if (arg.entry_kind != print_entry_values_only)
    674 	    print_frame_arg (&arg);
    675 
    676 	  if (entryarg.entry_kind != print_entry_values_no)
    677 	    {
    678 	      if (arg.entry_kind != print_entry_values_only)
    679 		{
    680 		  ui_out_text (uiout, ", ");
    681 		  ui_out_wrap_hint (uiout, "    ");
    682 		}
    683 
    684 	      print_frame_arg (&entryarg);
    685 	    }
    686 
    687 	  xfree (arg.error);
    688 	  xfree (entryarg.error);
    689 
    690 	  first = 0;
    691 	}
    692     }
    693 
    694   /* Don't print nameless args in situations where we don't know
    695      enough about the stack to find them.  */
    696   if (num != -1)
    697     {
    698       long start;
    699 
    700       if (highest_offset == -1)
    701 	start = gdbarch_frame_args_skip (get_frame_arch (frame));
    702       else
    703 	start = highest_offset;
    704 
    705       print_frame_nameless_args (frame, start, num - args_printed,
    706 				 first, stream);
    707     }
    708 
    709   do_cleanups (old_chain);
    710 }
    711 
    712 /* Set the current source and line to the location given by frame
    713    FRAME, if possible.  When CENTER is true, adjust so the relevant
    714    line is in the center of the next 'list'.  */
    715 
    716 void
    717 set_current_sal_from_frame (struct frame_info *frame)
    718 {
    719   struct symtab_and_line sal;
    720 
    721   find_frame_sal (frame, &sal);
    722   if (sal.symtab != NULL)
    723     set_current_source_symtab_and_line (&sal);
    724 }
    725 
    726 /* If ON, GDB will display disassembly of the next source line when
    727    execution of the program being debugged stops.
    728    If AUTO (which is the default), or there's no line info to determine
    729    the source line of the next instruction, display disassembly of next
    730    instruction instead.  */
    731 
    732 static enum auto_boolean disassemble_next_line;
    733 
    734 static void
    735 show_disassemble_next_line (struct ui_file *file, int from_tty,
    736 				 struct cmd_list_element *c,
    737 				 const char *value)
    738 {
    739   fprintf_filtered (file,
    740 		    _("Debugger's willingness to use "
    741 		      "disassemble-next-line is %s.\n"),
    742                     value);
    743 }
    744 
    745 /* Use TRY_CATCH to catch the exception from the gdb_disassembly
    746    because it will be broken by filter sometime.  */
    747 
    748 static void
    749 do_gdb_disassembly (struct gdbarch *gdbarch,
    750 		    int how_many, CORE_ADDR low, CORE_ADDR high)
    751 {
    752   volatile struct gdb_exception exception;
    753 
    754   TRY_CATCH (exception, RETURN_MASK_ERROR)
    755     {
    756       gdb_disassembly (gdbarch, current_uiout, 0,
    757 		       DISASSEMBLY_RAW_INSN, how_many,
    758 		       low, high);
    759     }
    760   if (exception.reason < 0)
    761     {
    762       /* If an exception was thrown while doing the disassembly, print
    763 	 the error message, to give the user a clue of what happened.  */
    764       exception_print (gdb_stderr, exception);
    765     }
    766 }
    767 
    768 /* Print information about frame FRAME.  The output is format according
    769    to PRINT_LEVEL and PRINT_WHAT and PRINT_ARGS.  The meaning of
    770    PRINT_WHAT is:
    771 
    772    SRC_LINE: Print only source line.
    773    LOCATION: Print only location.
    774    LOC_AND_SRC: Print location and source line.
    775 
    776    Used in "where" output, and to emit breakpoint or step
    777    messages.  */
    778 
    779 void
    780 print_frame_info (struct frame_info *frame, int print_level,
    781 		  enum print_what print_what, int print_args,
    782 		  int set_current_sal)
    783 {
    784   struct gdbarch *gdbarch = get_frame_arch (frame);
    785   struct symtab_and_line sal;
    786   int source_print;
    787   int location_print;
    788   struct ui_out *uiout = current_uiout;
    789 
    790   if (get_frame_type (frame) == DUMMY_FRAME
    791       || get_frame_type (frame) == SIGTRAMP_FRAME
    792       || get_frame_type (frame) == ARCH_FRAME)
    793     {
    794       struct cleanup *uiout_cleanup
    795 	= make_cleanup_ui_out_tuple_begin_end (uiout, "frame");
    796 
    797       annotate_frame_begin (print_level ? frame_relative_level (frame) : 0,
    798 			    gdbarch, get_frame_pc (frame));
    799 
    800       /* Do this regardless of SOURCE because we don't have any source
    801          to list for this frame.  */
    802       if (print_level)
    803         {
    804           ui_out_text (uiout, "#");
    805           ui_out_field_fmt_int (uiout, 2, ui_left, "level",
    806 				frame_relative_level (frame));
    807         }
    808       if (ui_out_is_mi_like_p (uiout))
    809         {
    810           annotate_frame_address ();
    811           ui_out_field_core_addr (uiout, "addr",
    812 				  gdbarch, get_frame_pc (frame));
    813           annotate_frame_address_end ();
    814         }
    815 
    816       if (get_frame_type (frame) == DUMMY_FRAME)
    817         {
    818           annotate_function_call ();
    819           ui_out_field_string (uiout, "func", "<function called from gdb>");
    820 	}
    821       else if (get_frame_type (frame) == SIGTRAMP_FRAME)
    822         {
    823 	  annotate_signal_handler_caller ();
    824           ui_out_field_string (uiout, "func", "<signal handler called>");
    825         }
    826       else if (get_frame_type (frame) == ARCH_FRAME)
    827         {
    828           ui_out_field_string (uiout, "func", "<cross-architecture call>");
    829 	}
    830       ui_out_text (uiout, "\n");
    831       annotate_frame_end ();
    832 
    833       /* If disassemble-next-line is set to auto or on output the next
    834 	 instruction.  */
    835       if (disassemble_next_line == AUTO_BOOLEAN_AUTO
    836 	  || disassemble_next_line == AUTO_BOOLEAN_TRUE)
    837 	do_gdb_disassembly (get_frame_arch (frame), 1,
    838 			    get_frame_pc (frame), get_frame_pc (frame) + 1);
    839 
    840       do_cleanups (uiout_cleanup);
    841       return;
    842     }
    843 
    844   /* If FRAME is not the innermost frame, that normally means that
    845      FRAME->pc points to *after* the call instruction, and we want to
    846      get the line containing the call, never the next line.  But if
    847      the next frame is a SIGTRAMP_FRAME or a DUMMY_FRAME, then the
    848      next frame was not entered as the result of a call, and we want
    849      to get the line containing FRAME->pc.  */
    850   find_frame_sal (frame, &sal);
    851 
    852   location_print = (print_what == LOCATION
    853 		    || print_what == LOC_AND_ADDRESS
    854 		    || print_what == SRC_AND_LOC);
    855 
    856   if (location_print || !sal.symtab)
    857     print_frame (frame, print_level, print_what, print_args, sal);
    858 
    859   source_print = (print_what == SRC_LINE || print_what == SRC_AND_LOC);
    860 
    861   /* If disassemble-next-line is set to auto or on and doesn't have
    862      the line debug messages for $pc, output the next instruction.  */
    863   if ((disassemble_next_line == AUTO_BOOLEAN_AUTO
    864        || disassemble_next_line == AUTO_BOOLEAN_TRUE)
    865       && source_print && !sal.symtab)
    866     do_gdb_disassembly (get_frame_arch (frame), 1,
    867 			get_frame_pc (frame), get_frame_pc (frame) + 1);
    868 
    869   if (source_print && sal.symtab)
    870     {
    871       int done = 0;
    872       int mid_statement = ((print_what == SRC_LINE)
    873 			   && frame_show_address (frame, sal));
    874 
    875       if (annotation_level)
    876 	done = identify_source_line (sal.symtab, sal.line, mid_statement,
    877 				     get_frame_pc (frame));
    878       if (!done)
    879 	{
    880 	  if (deprecated_print_frame_info_listing_hook)
    881 	    deprecated_print_frame_info_listing_hook (sal.symtab,
    882 						      sal.line,
    883 						      sal.line + 1, 0);
    884 	  else
    885 	    {
    886 	      struct value_print_options opts;
    887 
    888 	      get_user_print_options (&opts);
    889 	      /* We used to do this earlier, but that is clearly
    890 		 wrong.  This function is used by many different
    891 		 parts of gdb, including normal_stop in infrun.c,
    892 		 which uses this to print out the current PC
    893 		 when we stepi/nexti into the middle of a source
    894 		 line.  Only the command line really wants this
    895 		 behavior.  Other UIs probably would like the
    896 		 ability to decide for themselves if it is desired.  */
    897 	      if (opts.addressprint && mid_statement)
    898 		{
    899 		  ui_out_field_core_addr (uiout, "addr",
    900 					  gdbarch, get_frame_pc (frame));
    901 		  ui_out_text (uiout, "\t");
    902 		}
    903 
    904 	      print_source_lines (sal.symtab, sal.line, sal.line + 1, 0);
    905 	    }
    906 	}
    907 
    908       /* If disassemble-next-line is set to on and there is line debug
    909          messages, output assembly codes for next line.  */
    910       if (disassemble_next_line == AUTO_BOOLEAN_TRUE)
    911 	do_gdb_disassembly (get_frame_arch (frame), -1, sal.pc, sal.end);
    912     }
    913 
    914   if (set_current_sal)
    915     {
    916       CORE_ADDR pc;
    917 
    918       if (get_frame_pc_if_available (frame, &pc))
    919 	set_last_displayed_sal (1, sal.pspace, pc, sal.symtab, sal.line);
    920       else
    921 	set_last_displayed_sal (0, 0, 0, 0, 0);
    922     }
    923 
    924   annotate_frame_end ();
    925 
    926   gdb_flush (gdb_stdout);
    927 }
    928 
    929 /* Remember the last symtab and line we displayed, which we use e.g.
    930  * as the place to put a breakpoint when the `break' command is
    931  * invoked with no arguments.  */
    932 
    933 static void
    934 set_last_displayed_sal (int valid, struct program_space *pspace,
    935 			CORE_ADDR addr, struct symtab *symtab,
    936 			int line)
    937 {
    938   last_displayed_sal_valid = valid;
    939   last_displayed_pspace = pspace;
    940   last_displayed_addr = addr;
    941   last_displayed_symtab = symtab;
    942   last_displayed_line = line;
    943   if (valid && pspace == NULL)
    944     {
    945       clear_last_displayed_sal ();
    946       internal_error (__FILE__, __LINE__,
    947 		      _("Trying to set NULL pspace."));
    948     }
    949 }
    950 
    951 /* Forget the last sal we displayed.  */
    952 
    953 void
    954 clear_last_displayed_sal (void)
    955 {
    956   last_displayed_sal_valid = 0;
    957   last_displayed_pspace = 0;
    958   last_displayed_addr = 0;
    959   last_displayed_symtab = 0;
    960   last_displayed_line = 0;
    961 }
    962 
    963 /* Is our record of the last sal we displayed valid?  If not,
    964  * the get_last_displayed_* functions will return NULL or 0, as
    965  * appropriate.  */
    966 
    967 int
    968 last_displayed_sal_is_valid (void)
    969 {
    970   return last_displayed_sal_valid;
    971 }
    972 
    973 /* Get the pspace of the last sal we displayed, if it's valid.  */
    974 
    975 struct program_space *
    976 get_last_displayed_pspace (void)
    977 {
    978   if (last_displayed_sal_valid)
    979     return last_displayed_pspace;
    980   return 0;
    981 }
    982 
    983 /* Get the address of the last sal we displayed, if it's valid.  */
    984 
    985 CORE_ADDR
    986 get_last_displayed_addr (void)
    987 {
    988   if (last_displayed_sal_valid)
    989     return last_displayed_addr;
    990   return 0;
    991 }
    992 
    993 /* Get the symtab of the last sal we displayed, if it's valid.  */
    994 
    995 struct symtab*
    996 get_last_displayed_symtab (void)
    997 {
    998   if (last_displayed_sal_valid)
    999     return last_displayed_symtab;
   1000   return 0;
   1001 }
   1002 
   1003 /* Get the line of the last sal we displayed, if it's valid.  */
   1004 
   1005 int
   1006 get_last_displayed_line (void)
   1007 {
   1008   if (last_displayed_sal_valid)
   1009     return last_displayed_line;
   1010   return 0;
   1011 }
   1012 
   1013 /* Get the last sal we displayed, if it's valid.  */
   1014 
   1015 void
   1016 get_last_displayed_sal (struct symtab_and_line *sal)
   1017 {
   1018   if (last_displayed_sal_valid)
   1019     {
   1020       sal->pspace = last_displayed_pspace;
   1021       sal->pc = last_displayed_addr;
   1022       sal->symtab = last_displayed_symtab;
   1023       sal->line = last_displayed_line;
   1024     }
   1025   else
   1026     {
   1027       sal->pspace = 0;
   1028       sal->pc = 0;
   1029       sal->symtab = 0;
   1030       sal->line = 0;
   1031     }
   1032 }
   1033 
   1034 
   1035 /* Attempt to obtain the FUNNAME, FUNLANG and optionally FUNCP of the function
   1036    corresponding to FRAME.  FUNNAME needs to be freed by the caller.  */
   1037 
   1038 void
   1039 find_frame_funname (struct frame_info *frame, char **funname,
   1040 		    enum language *funlang, struct symbol **funcp)
   1041 {
   1042   struct symbol *func;
   1043 
   1044   *funname = NULL;
   1045   *funlang = language_unknown;
   1046   if (funcp)
   1047     *funcp = NULL;
   1048 
   1049   func = get_frame_function (frame);
   1050   if (func)
   1051     {
   1052       /* In certain pathological cases, the symtabs give the wrong
   1053          function (when we are in the first function in a file which
   1054          is compiled without debugging symbols, the previous function
   1055          is compiled with debugging symbols, and the "foo.o" symbol
   1056          that is supposed to tell us where the file with debugging
   1057          symbols ends has been truncated by ar because it is longer
   1058          than 15 characters).  This also occurs if the user uses asm()
   1059          to create a function but not stabs for it (in a file compiled
   1060          with -g).
   1061 
   1062          So look in the minimal symbol tables as well, and if it comes
   1063          up with a larger address for the function use that instead.
   1064          I don't think this can ever cause any problems; there
   1065          shouldn't be any minimal symbols in the middle of a function;
   1066          if this is ever changed many parts of GDB will need to be
   1067          changed (and we'll create a find_pc_minimal_function or some
   1068          such).  */
   1069 
   1070       struct bound_minimal_symbol msymbol;
   1071 
   1072       /* Don't attempt to do this for inlined functions, which do not
   1073 	 have a corresponding minimal symbol.  */
   1074       if (!block_inlined_p (SYMBOL_BLOCK_VALUE (func)))
   1075 	msymbol
   1076 	  = lookup_minimal_symbol_by_pc (get_frame_address_in_block (frame));
   1077       else
   1078 	memset (&msymbol, 0, sizeof (msymbol));
   1079 
   1080       if (msymbol.minsym != NULL
   1081 	  && (BMSYMBOL_VALUE_ADDRESS (msymbol)
   1082 	      > BLOCK_START (SYMBOL_BLOCK_VALUE (func))))
   1083 	{
   1084 	  /* We also don't know anything about the function besides
   1085 	     its address and name.  */
   1086 	  func = 0;
   1087 	  *funname = xstrdup (MSYMBOL_PRINT_NAME (msymbol.minsym));
   1088 	  *funlang = MSYMBOL_LANGUAGE (msymbol.minsym);
   1089 	}
   1090       else
   1091 	{
   1092 	  *funname = xstrdup (SYMBOL_PRINT_NAME (func));
   1093 	  *funlang = SYMBOL_LANGUAGE (func);
   1094 	  if (funcp)
   1095 	    *funcp = func;
   1096 	  if (*funlang == language_cplus)
   1097 	    {
   1098 	      /* It seems appropriate to use SYMBOL_PRINT_NAME() here,
   1099 		 to display the demangled name that we already have
   1100 		 stored in the symbol table, but we stored a version
   1101 		 with DMGL_PARAMS turned on, and here we don't want to
   1102 		 display parameters.  So remove the parameters.  */
   1103 	      char *func_only = cp_remove_params (*funname);
   1104 
   1105 	      if (func_only)
   1106 		{
   1107 		  xfree (*funname);
   1108 		  *funname = func_only;
   1109 		}
   1110 	    }
   1111 	}
   1112     }
   1113   else
   1114     {
   1115       struct bound_minimal_symbol msymbol;
   1116       CORE_ADDR pc;
   1117 
   1118       if (!get_frame_address_in_block_if_available (frame, &pc))
   1119 	return;
   1120 
   1121       msymbol = lookup_minimal_symbol_by_pc (pc);
   1122       if (msymbol.minsym != NULL)
   1123 	{
   1124 	  *funname = xstrdup (MSYMBOL_PRINT_NAME (msymbol.minsym));
   1125 	  *funlang = MSYMBOL_LANGUAGE (msymbol.minsym);
   1126 	}
   1127     }
   1128 }
   1129 
   1130 static void
   1131 print_frame (struct frame_info *frame, int print_level,
   1132 	     enum print_what print_what, int print_args,
   1133 	     struct symtab_and_line sal)
   1134 {
   1135   struct gdbarch *gdbarch = get_frame_arch (frame);
   1136   struct ui_out *uiout = current_uiout;
   1137   char *funname = NULL;
   1138   enum language funlang = language_unknown;
   1139   struct ui_file *stb;
   1140   struct cleanup *old_chain, *list_chain;
   1141   struct value_print_options opts;
   1142   struct symbol *func;
   1143   CORE_ADDR pc = 0;
   1144   int pc_p;
   1145 
   1146   pc_p = get_frame_pc_if_available (frame, &pc);
   1147 
   1148   stb = mem_fileopen ();
   1149   old_chain = make_cleanup_ui_file_delete (stb);
   1150 
   1151   find_frame_funname (frame, &funname, &funlang, &func);
   1152   make_cleanup (xfree, funname);
   1153 
   1154   annotate_frame_begin (print_level ? frame_relative_level (frame) : 0,
   1155 			gdbarch, pc);
   1156 
   1157   list_chain = make_cleanup_ui_out_tuple_begin_end (uiout, "frame");
   1158 
   1159   if (print_level)
   1160     {
   1161       ui_out_text (uiout, "#");
   1162       ui_out_field_fmt_int (uiout, 2, ui_left, "level",
   1163 			    frame_relative_level (frame));
   1164     }
   1165   get_user_print_options (&opts);
   1166   if (opts.addressprint)
   1167     if (!sal.symtab
   1168 	|| frame_show_address (frame, sal)
   1169 	|| print_what == LOC_AND_ADDRESS)
   1170       {
   1171 	annotate_frame_address ();
   1172 	if (pc_p)
   1173 	  ui_out_field_core_addr (uiout, "addr", gdbarch, pc);
   1174 	else
   1175 	  ui_out_field_string (uiout, "addr", "<unavailable>");
   1176 	annotate_frame_address_end ();
   1177 	ui_out_text (uiout, " in ");
   1178       }
   1179   annotate_frame_function_name ();
   1180   fprintf_symbol_filtered (stb, funname ? funname : "??",
   1181 			   funlang, DMGL_ANSI);
   1182   ui_out_field_stream (uiout, "func", stb);
   1183   ui_out_wrap_hint (uiout, "   ");
   1184   annotate_frame_args ();
   1185 
   1186   ui_out_text (uiout, " (");
   1187   if (print_args)
   1188     {
   1189       struct gdbarch *gdbarch = get_frame_arch (frame);
   1190       int numargs;
   1191       struct cleanup *args_list_chain;
   1192       volatile struct gdb_exception e;
   1193 
   1194       if (gdbarch_frame_num_args_p (gdbarch))
   1195 	{
   1196 	  numargs = gdbarch_frame_num_args (gdbarch, frame);
   1197 	  gdb_assert (numargs >= 0);
   1198 	}
   1199       else
   1200 	numargs = -1;
   1201 
   1202       args_list_chain = make_cleanup_ui_out_list_begin_end (uiout, "args");
   1203       TRY_CATCH (e, RETURN_MASK_ERROR)
   1204 	{
   1205 	  print_frame_args (func, frame, numargs, gdb_stdout);
   1206 	}
   1207       /* FIXME: ARGS must be a list.  If one argument is a string it
   1208 	  will have " that will not be properly escaped.  */
   1209       /* Invoke ui_out_tuple_end.  */
   1210       do_cleanups (args_list_chain);
   1211       QUIT;
   1212     }
   1213   ui_out_text (uiout, ")");
   1214   if (sal.symtab)
   1215     {
   1216       const char *filename_display;
   1217 
   1218       filename_display = symtab_to_filename_for_display (sal.symtab);
   1219       annotate_frame_source_begin ();
   1220       ui_out_wrap_hint (uiout, "   ");
   1221       ui_out_text (uiout, " at ");
   1222       annotate_frame_source_file ();
   1223       ui_out_field_string (uiout, "file", filename_display);
   1224       if (ui_out_is_mi_like_p (uiout))
   1225 	{
   1226 	  const char *fullname = symtab_to_fullname (sal.symtab);
   1227 
   1228 	  ui_out_field_string (uiout, "fullname", fullname);
   1229 	}
   1230       annotate_frame_source_file_end ();
   1231       ui_out_text (uiout, ":");
   1232       annotate_frame_source_line ();
   1233       ui_out_field_int (uiout, "line", sal.line);
   1234       annotate_frame_source_end ();
   1235     }
   1236 
   1237   if (pc_p && (funname == NULL || sal.symtab == NULL))
   1238     {
   1239       char *lib = solib_name_from_address (get_frame_program_space (frame),
   1240 					   get_frame_pc (frame));
   1241 
   1242       if (lib)
   1243 	{
   1244 	  annotate_frame_where ();
   1245 	  ui_out_wrap_hint (uiout, "  ");
   1246 	  ui_out_text (uiout, " from ");
   1247 	  ui_out_field_string (uiout, "from", lib);
   1248 	}
   1249     }
   1250 
   1251   /* do_cleanups will call ui_out_tuple_end() for us.  */
   1252   do_cleanups (list_chain);
   1253   ui_out_text (uiout, "\n");
   1254   do_cleanups (old_chain);
   1255 }
   1256 
   1257 
   1259 /* Read a frame specification in whatever the appropriate format is
   1260    from FRAME_EXP.  Call error(), printing MESSAGE, if the
   1261    specification is in any way invalid (so this function never returns
   1262    NULL).  When SEPECTED_P is non-NULL set its target to indicate that
   1263    the default selected frame was used.  */
   1264 
   1265 static struct frame_info *
   1266 parse_frame_specification_1 (const char *frame_exp, const char *message,
   1267 			     int *selected_frame_p)
   1268 {
   1269   int numargs;
   1270   struct value *args[4];
   1271   CORE_ADDR addrs[ARRAY_SIZE (args)];
   1272 
   1273   if (frame_exp == NULL)
   1274     numargs = 0;
   1275   else
   1276     {
   1277       numargs = 0;
   1278       while (1)
   1279 	{
   1280 	  char *addr_string;
   1281 	  struct cleanup *cleanup;
   1282 	  const char *p;
   1283 
   1284 	  /* Skip leading white space, bail of EOL.  */
   1285 	  frame_exp = skip_spaces_const (frame_exp);
   1286 	  if (!*frame_exp)
   1287 	    break;
   1288 
   1289 	  /* Parse the argument, extract it, save it.  */
   1290 	  for (p = frame_exp;
   1291 	       *p && !isspace (*p);
   1292 	       p++);
   1293 	  addr_string = savestring (frame_exp, p - frame_exp);
   1294 	  frame_exp = p;
   1295 	  cleanup = make_cleanup (xfree, addr_string);
   1296 
   1297 	  /* NOTE: Parse and evaluate expression, but do not use
   1298 	     functions such as parse_and_eval_long or
   1299 	     parse_and_eval_address to also extract the value.
   1300 	     Instead value_as_long and value_as_address are used.
   1301 	     This avoids problems with expressions that contain
   1302 	     side-effects.  */
   1303 	  if (numargs >= ARRAY_SIZE (args))
   1304 	    error (_("Too many args in frame specification"));
   1305 	  args[numargs++] = parse_and_eval (addr_string);
   1306 
   1307 	  do_cleanups (cleanup);
   1308 	}
   1309     }
   1310 
   1311   /* If no args, default to the selected frame.  */
   1312   if (numargs == 0)
   1313     {
   1314       if (selected_frame_p != NULL)
   1315 	(*selected_frame_p) = 1;
   1316       return get_selected_frame (message);
   1317     }
   1318 
   1319   /* None of the remaining use the selected frame.  */
   1320   if (selected_frame_p != NULL)
   1321     (*selected_frame_p) = 0;
   1322 
   1323   /* Assume the single arg[0] is an integer, and try using that to
   1324      select a frame relative to current.  */
   1325   if (numargs == 1)
   1326     {
   1327       struct frame_info *fid;
   1328       int level = value_as_long (args[0]);
   1329 
   1330       fid = find_relative_frame (get_current_frame (), &level);
   1331       if (level == 0)
   1332 	/* find_relative_frame was successful.  */
   1333 	return fid;
   1334     }
   1335 
   1336   /* Convert each value into a corresponding address.  */
   1337   {
   1338     int i;
   1339 
   1340     for (i = 0; i < numargs; i++)
   1341       addrs[i] = value_as_address (args[i]);
   1342   }
   1343 
   1344   /* Assume that the single arg[0] is an address, use that to identify
   1345      a frame with a matching ID.  Should this also accept stack/pc or
   1346      stack/pc/special.  */
   1347   if (numargs == 1)
   1348     {
   1349       struct frame_id id = frame_id_build_wild (addrs[0]);
   1350       struct frame_info *fid;
   1351 
   1352       /* If (s)he specifies the frame with an address, he deserves
   1353 	 what (s)he gets.  Still, give the highest one that matches.
   1354 	 (NOTE: cagney/2004-10-29: Why highest, or outer-most, I don't
   1355 	 know).  */
   1356       for (fid = get_current_frame ();
   1357 	   fid != NULL;
   1358 	   fid = get_prev_frame (fid))
   1359 	{
   1360 	  if (frame_id_eq (id, get_frame_id (fid)))
   1361 	    {
   1362 	      struct frame_info *prev_frame;
   1363 
   1364 	      while (1)
   1365 		{
   1366 		  prev_frame = get_prev_frame (fid);
   1367 		  if (!prev_frame
   1368 		      || !frame_id_eq (id, get_frame_id (prev_frame)))
   1369 		    break;
   1370 		  fid = prev_frame;
   1371 		}
   1372 	      return fid;
   1373 	    }
   1374 	}
   1375       }
   1376 
   1377   /* We couldn't identify the frame as an existing frame, but
   1378      perhaps we can create one with a single argument.  */
   1379   if (numargs == 1)
   1380     return create_new_frame (addrs[0], 0);
   1381   else if (numargs == 2)
   1382     return create_new_frame (addrs[0], addrs[1]);
   1383   else
   1384     error (_("Too many args in frame specification"));
   1385 }
   1386 
   1387 static struct frame_info *
   1388 parse_frame_specification (char *frame_exp)
   1389 {
   1390   return parse_frame_specification_1 (frame_exp, NULL, NULL);
   1391 }
   1392 
   1393 /* Print verbosely the selected frame or the frame at address
   1394    ADDR_EXP.  Absolutely all information in the frame is printed.  */
   1395 
   1396 static void
   1397 frame_info (char *addr_exp, int from_tty)
   1398 {
   1399   struct frame_info *fi;
   1400   struct symtab_and_line sal;
   1401   struct symbol *func;
   1402   struct symtab *s;
   1403   struct frame_info *calling_frame_info;
   1404   int numregs;
   1405   const char *funname = 0;
   1406   enum language funlang = language_unknown;
   1407   const char *pc_regname;
   1408   int selected_frame_p;
   1409   struct gdbarch *gdbarch;
   1410   struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
   1411   CORE_ADDR frame_pc;
   1412   int frame_pc_p;
   1413   /* Initialize it to avoid "may be used uninitialized" warning.  */
   1414   CORE_ADDR caller_pc = 0;
   1415   volatile struct gdb_exception ex;
   1416 
   1417   fi = parse_frame_specification_1 (addr_exp, "No stack.", &selected_frame_p);
   1418   gdbarch = get_frame_arch (fi);
   1419 
   1420   /* Name of the value returned by get_frame_pc().  Per comments, "pc"
   1421      is not a good name.  */
   1422   if (gdbarch_pc_regnum (gdbarch) >= 0)
   1423     /* OK, this is weird.  The gdbarch_pc_regnum hardware register's value can
   1424        easily not match that of the internal value returned by
   1425        get_frame_pc().  */
   1426     pc_regname = gdbarch_register_name (gdbarch, gdbarch_pc_regnum (gdbarch));
   1427   else
   1428     /* But then, this is weird to.  Even without gdbarch_pc_regnum, an
   1429        architectures will often have a hardware register called "pc",
   1430        and that register's value, again, can easily not match
   1431        get_frame_pc().  */
   1432     pc_regname = "pc";
   1433 
   1434   frame_pc_p = get_frame_pc_if_available (fi, &frame_pc);
   1435   find_frame_sal (fi, &sal);
   1436   func = get_frame_function (fi);
   1437   s = sal.symtab;
   1438   if (func)
   1439     {
   1440       funname = SYMBOL_PRINT_NAME (func);
   1441       funlang = SYMBOL_LANGUAGE (func);
   1442       if (funlang == language_cplus)
   1443 	{
   1444 	  /* It seems appropriate to use SYMBOL_PRINT_NAME() here,
   1445 	     to display the demangled name that we already have
   1446 	     stored in the symbol table, but we stored a version
   1447 	     with DMGL_PARAMS turned on, and here we don't want to
   1448 	     display parameters.  So remove the parameters.  */
   1449 	  char *func_only = cp_remove_params (funname);
   1450 
   1451 	  if (func_only)
   1452 	    {
   1453 	      funname = func_only;
   1454 	      make_cleanup (xfree, func_only);
   1455 	    }
   1456 	}
   1457     }
   1458   else if (frame_pc_p)
   1459     {
   1460       struct bound_minimal_symbol msymbol;
   1461 
   1462       msymbol = lookup_minimal_symbol_by_pc (frame_pc);
   1463       if (msymbol.minsym != NULL)
   1464 	{
   1465 	  funname = MSYMBOL_PRINT_NAME (msymbol.minsym);
   1466 	  funlang = MSYMBOL_LANGUAGE (msymbol.minsym);
   1467 	}
   1468     }
   1469   calling_frame_info = get_prev_frame (fi);
   1470 
   1471   if (selected_frame_p && frame_relative_level (fi) >= 0)
   1472     {
   1473       printf_filtered (_("Stack level %d, frame at "),
   1474 		       frame_relative_level (fi));
   1475     }
   1476   else
   1477     {
   1478       printf_filtered (_("Stack frame at "));
   1479     }
   1480   fputs_filtered (paddress (gdbarch, get_frame_base (fi)), gdb_stdout);
   1481   printf_filtered (":\n");
   1482   printf_filtered (" %s = ", pc_regname);
   1483   if (frame_pc_p)
   1484     fputs_filtered (paddress (gdbarch, get_frame_pc (fi)), gdb_stdout);
   1485   else
   1486     fputs_filtered ("<unavailable>", gdb_stdout);
   1487 
   1488   wrap_here ("   ");
   1489   if (funname)
   1490     {
   1491       printf_filtered (" in ");
   1492       fprintf_symbol_filtered (gdb_stdout, funname, funlang,
   1493 			       DMGL_ANSI | DMGL_PARAMS);
   1494     }
   1495   wrap_here ("   ");
   1496   if (sal.symtab)
   1497     printf_filtered (" (%s:%d)", symtab_to_filename_for_display (sal.symtab),
   1498 		     sal.line);
   1499   puts_filtered ("; ");
   1500   wrap_here ("    ");
   1501   printf_filtered ("saved %s = ", pc_regname);
   1502 
   1503   TRY_CATCH (ex, RETURN_MASK_ERROR)
   1504     {
   1505       caller_pc = frame_unwind_caller_pc (fi);
   1506     }
   1507   if (ex.reason < 0)
   1508     {
   1509       switch (ex.error)
   1510 	{
   1511 	case NOT_AVAILABLE_ERROR:
   1512 	  val_print_unavailable (gdb_stdout);
   1513 	  break;
   1514 	case OPTIMIZED_OUT_ERROR:
   1515 	  val_print_not_saved (gdb_stdout);
   1516 	  break;
   1517 	default:
   1518 	  fprintf_filtered (gdb_stdout, _("<error: %s>"), ex.message);
   1519 	  break;
   1520 	}
   1521     }
   1522   else
   1523     fputs_filtered (paddress (gdbarch, caller_pc), gdb_stdout);
   1524   printf_filtered ("\n");
   1525 
   1526   if (calling_frame_info == NULL)
   1527     {
   1528       enum unwind_stop_reason reason;
   1529 
   1530       reason = get_frame_unwind_stop_reason (fi);
   1531       if (reason != UNWIND_NO_REASON)
   1532 	printf_filtered (_(" Outermost frame: %s\n"),
   1533 			 frame_stop_reason_string (fi));
   1534     }
   1535   else if (get_frame_type (fi) == TAILCALL_FRAME)
   1536     puts_filtered (" tail call frame");
   1537   else if (get_frame_type (fi) == INLINE_FRAME)
   1538     printf_filtered (" inlined into frame %d",
   1539 		     frame_relative_level (get_prev_frame (fi)));
   1540   else
   1541     {
   1542       printf_filtered (" called by frame at ");
   1543       fputs_filtered (paddress (gdbarch, get_frame_base (calling_frame_info)),
   1544 		      gdb_stdout);
   1545     }
   1546   if (get_next_frame (fi) && calling_frame_info)
   1547     puts_filtered (",");
   1548   wrap_here ("   ");
   1549   if (get_next_frame (fi))
   1550     {
   1551       printf_filtered (" caller of frame at ");
   1552       fputs_filtered (paddress (gdbarch, get_frame_base (get_next_frame (fi))),
   1553 		      gdb_stdout);
   1554     }
   1555   if (get_next_frame (fi) || calling_frame_info)
   1556     puts_filtered ("\n");
   1557 
   1558   if (s)
   1559     printf_filtered (" source language %s.\n",
   1560 		     language_str (s->language));
   1561 
   1562   {
   1563     /* Address of the argument list for this frame, or 0.  */
   1564     CORE_ADDR arg_list = get_frame_args_address (fi);
   1565     /* Number of args for this frame, or -1 if unknown.  */
   1566     int numargs;
   1567 
   1568     if (arg_list == 0)
   1569       printf_filtered (" Arglist at unknown address.\n");
   1570     else
   1571       {
   1572 	printf_filtered (" Arglist at ");
   1573 	fputs_filtered (paddress (gdbarch, arg_list), gdb_stdout);
   1574 	printf_filtered (",");
   1575 
   1576 	if (!gdbarch_frame_num_args_p (gdbarch))
   1577 	  {
   1578 	    numargs = -1;
   1579 	    puts_filtered (" args: ");
   1580 	  }
   1581 	else
   1582 	  {
   1583 	    numargs = gdbarch_frame_num_args (gdbarch, fi);
   1584 	    gdb_assert (numargs >= 0);
   1585 	    if (numargs == 0)
   1586 	      puts_filtered (" no args.");
   1587 	    else if (numargs == 1)
   1588 	      puts_filtered (" 1 arg: ");
   1589 	    else
   1590 	      printf_filtered (" %d args: ", numargs);
   1591 	  }
   1592 	print_frame_args (func, fi, numargs, gdb_stdout);
   1593 	puts_filtered ("\n");
   1594       }
   1595   }
   1596   {
   1597     /* Address of the local variables for this frame, or 0.  */
   1598     CORE_ADDR arg_list = get_frame_locals_address (fi);
   1599 
   1600     if (arg_list == 0)
   1601       printf_filtered (" Locals at unknown address,");
   1602     else
   1603       {
   1604 	printf_filtered (" Locals at ");
   1605 	fputs_filtered (paddress (gdbarch, arg_list), gdb_stdout);
   1606 	printf_filtered (",");
   1607       }
   1608   }
   1609 
   1610   /* Print as much information as possible on the location of all the
   1611      registers.  */
   1612   {
   1613     enum lval_type lval;
   1614     int optimized;
   1615     int unavailable;
   1616     CORE_ADDR addr;
   1617     int realnum;
   1618     int count;
   1619     int i;
   1620     int need_nl = 1;
   1621 
   1622     /* The sp is special; what's displayed isn't the save address, but
   1623        the value of the previous frame's sp.  This is a legacy thing,
   1624        at one stage the frame cached the previous frame's SP instead
   1625        of its address, hence it was easiest to just display the cached
   1626        value.  */
   1627     if (gdbarch_sp_regnum (gdbarch) >= 0)
   1628       {
   1629 	/* Find out the location of the saved stack pointer with out
   1630            actually evaluating it.  */
   1631 	frame_register_unwind (fi, gdbarch_sp_regnum (gdbarch),
   1632 			       &optimized, &unavailable, &lval, &addr,
   1633 			       &realnum, NULL);
   1634 	if (!optimized && !unavailable && lval == not_lval)
   1635 	  {
   1636 	    enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   1637 	    int sp_size = register_size (gdbarch, gdbarch_sp_regnum (gdbarch));
   1638 	    gdb_byte value[MAX_REGISTER_SIZE];
   1639 	    CORE_ADDR sp;
   1640 
   1641 	    frame_register_unwind (fi, gdbarch_sp_regnum (gdbarch),
   1642 				   &optimized, &unavailable, &lval, &addr,
   1643 				   &realnum, value);
   1644 	    /* NOTE: cagney/2003-05-22: This is assuming that the
   1645                stack pointer was packed as an unsigned integer.  That
   1646                may or may not be valid.  */
   1647 	    sp = extract_unsigned_integer (value, sp_size, byte_order);
   1648 	    printf_filtered (" Previous frame's sp is ");
   1649 	    fputs_filtered (paddress (gdbarch, sp), gdb_stdout);
   1650 	    printf_filtered ("\n");
   1651 	    need_nl = 0;
   1652 	  }
   1653 	else if (!optimized && !unavailable && lval == lval_memory)
   1654 	  {
   1655 	    printf_filtered (" Previous frame's sp at ");
   1656 	    fputs_filtered (paddress (gdbarch, addr), gdb_stdout);
   1657 	    printf_filtered ("\n");
   1658 	    need_nl = 0;
   1659 	  }
   1660 	else if (!optimized && !unavailable && lval == lval_register)
   1661 	  {
   1662 	    printf_filtered (" Previous frame's sp in %s\n",
   1663 			     gdbarch_register_name (gdbarch, realnum));
   1664 	    need_nl = 0;
   1665 	  }
   1666 	/* else keep quiet.  */
   1667       }
   1668 
   1669     count = 0;
   1670     numregs = gdbarch_num_regs (gdbarch)
   1671 	      + gdbarch_num_pseudo_regs (gdbarch);
   1672     for (i = 0; i < numregs; i++)
   1673       if (i != gdbarch_sp_regnum (gdbarch)
   1674 	  && gdbarch_register_reggroup_p (gdbarch, i, all_reggroup))
   1675 	{
   1676 	  /* Find out the location of the saved register without
   1677              fetching the corresponding value.  */
   1678 	  frame_register_unwind (fi, i, &optimized, &unavailable,
   1679 				 &lval, &addr, &realnum, NULL);
   1680 	  /* For moment, only display registers that were saved on the
   1681 	     stack.  */
   1682 	  if (!optimized && !unavailable && lval == lval_memory)
   1683 	    {
   1684 	      if (count == 0)
   1685 		puts_filtered (" Saved registers:\n ");
   1686 	      else
   1687 		puts_filtered (",");
   1688 	      wrap_here (" ");
   1689 	      printf_filtered (" %s at ",
   1690 			       gdbarch_register_name (gdbarch, i));
   1691 	      fputs_filtered (paddress (gdbarch, addr), gdb_stdout);
   1692 	      count++;
   1693 	    }
   1694 	}
   1695     if (count || need_nl)
   1696       puts_filtered ("\n");
   1697   }
   1698 
   1699   do_cleanups (back_to);
   1700 }
   1701 
   1702 /* Print briefly all stack frames or just the innermost COUNT_EXP
   1703    frames.  */
   1704 
   1705 static void
   1706 backtrace_command_1 (char *count_exp, int show_locals, int no_filters,
   1707 		     int from_tty)
   1708 {
   1709   struct frame_info *fi;
   1710   int count;
   1711   int i;
   1712   struct frame_info *trailing;
   1713   int trailing_level, py_start = 0, py_end = 0;
   1714   enum ext_lang_bt_status result = EXT_LANG_BT_ERROR;
   1715 
   1716   if (!target_has_stack)
   1717     error (_("No stack."));
   1718 
   1719   /* The following code must do two things.  First, it must set the
   1720      variable TRAILING to the frame from which we should start
   1721      printing.  Second, it must set the variable count to the number
   1722      of frames which we should print, or -1 if all of them.  */
   1723   trailing = get_current_frame ();
   1724 
   1725   trailing_level = 0;
   1726   if (count_exp)
   1727     {
   1728       count = parse_and_eval_long (count_exp);
   1729       if (count < 0)
   1730 	{
   1731 	  struct frame_info *current;
   1732 
   1733 	  py_start = count;
   1734 	  count = -count;
   1735 
   1736 	  current = trailing;
   1737 	  while (current && count--)
   1738 	    {
   1739 	      QUIT;
   1740 	      current = get_prev_frame (current);
   1741 	    }
   1742 
   1743 	  /* Will stop when CURRENT reaches the top of the stack.
   1744 	     TRAILING will be COUNT below it.  */
   1745 	  while (current)
   1746 	    {
   1747 	      QUIT;
   1748 	      trailing = get_prev_frame (trailing);
   1749 	      current = get_prev_frame (current);
   1750 	      trailing_level++;
   1751 	    }
   1752 
   1753 	  count = -1;
   1754 	}
   1755       else
   1756 	{
   1757 	  py_start = 0;
   1758 	  py_end = count;
   1759 	}
   1760     }
   1761   else
   1762     {
   1763       py_end = -1;
   1764       count = -1;
   1765     }
   1766 
   1767   if (info_verbose)
   1768     {
   1769       /* Read in symbols for all of the frames.  Need to do this in a
   1770          separate pass so that "Reading in symbols for xxx" messages
   1771          don't screw up the appearance of the backtrace.  Also if
   1772          people have strong opinions against reading symbols for
   1773          backtrace this may have to be an option.  */
   1774       i = count;
   1775       for (fi = trailing; fi != NULL && i--; fi = get_prev_frame (fi))
   1776 	{
   1777 	  CORE_ADDR pc;
   1778 
   1779 	  QUIT;
   1780 	  pc = get_frame_address_in_block (fi);
   1781 	  expand_symtab_containing_pc (pc, find_pc_mapped_section (pc));
   1782 	}
   1783     }
   1784 
   1785   if (! no_filters)
   1786     {
   1787       int flags = PRINT_LEVEL | PRINT_FRAME_INFO | PRINT_ARGS;
   1788       enum ext_lang_frame_args arg_type;
   1789 
   1790       if (show_locals)
   1791 	flags |= PRINT_LOCALS;
   1792 
   1793       if (!strcmp (print_frame_arguments, "scalars"))
   1794 	arg_type = CLI_SCALAR_VALUES;
   1795       else if (!strcmp (print_frame_arguments, "all"))
   1796 	arg_type = CLI_ALL_VALUES;
   1797       else
   1798 	arg_type = NO_VALUES;
   1799 
   1800       result = apply_ext_lang_frame_filter (get_current_frame (), flags,
   1801 					    arg_type, current_uiout,
   1802 					    py_start, py_end);
   1803     }
   1804 
   1805   /* Run the inbuilt backtrace if there are no filters registered, or
   1806      "no-filters" has been specified from the command.  */
   1807   if (no_filters ||  result == EXT_LANG_BT_NO_FILTERS)
   1808     {
   1809       for (i = 0, fi = trailing; fi && count--; i++, fi = get_prev_frame (fi))
   1810 	{
   1811 	  QUIT;
   1812 
   1813 	  /* Don't use print_stack_frame; if an error() occurs it probably
   1814 	     means further attempts to backtrace would fail (on the other
   1815 	     hand, perhaps the code does or could be fixed to make sure
   1816 	     the frame->prev field gets set to NULL in that case).  */
   1817 
   1818 	  print_frame_info (fi, 1, LOCATION, 1, 0);
   1819 	  if (show_locals)
   1820 	    {
   1821 	      struct frame_id frame_id = get_frame_id (fi);
   1822 
   1823 	      print_frame_local_vars (fi, 1, gdb_stdout);
   1824 
   1825 	      /* print_frame_local_vars invalidates FI.  */
   1826 	      fi = frame_find_by_id (frame_id);
   1827 	      if (fi == NULL)
   1828 		{
   1829 		  trailing = NULL;
   1830 		  warning (_("Unable to restore previously selected frame."));
   1831 		  break;
   1832 		}
   1833 	    }
   1834 
   1835 	  /* Save the last frame to check for error conditions.  */
   1836 	  trailing = fi;
   1837 	}
   1838 
   1839       /* If we've stopped before the end, mention that.  */
   1840       if (fi && from_tty)
   1841 	printf_filtered (_("(More stack frames follow...)\n"));
   1842 
   1843       /* If we've run out of frames, and the reason appears to be an error
   1844 	 condition, print it.  */
   1845       if (fi == NULL && trailing != NULL)
   1846 	{
   1847 	  enum unwind_stop_reason reason;
   1848 
   1849 	  reason = get_frame_unwind_stop_reason (trailing);
   1850 	  if (reason >= UNWIND_FIRST_ERROR)
   1851 	    printf_filtered (_("Backtrace stopped: %s\n"),
   1852 			     frame_stop_reason_string (trailing));
   1853 	}
   1854     }
   1855 }
   1856 
   1857 static void
   1858 backtrace_command (char *arg, int from_tty)
   1859 {
   1860   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
   1861   int fulltrace_arg = -1, arglen = 0, argc = 0, no_filters  = -1;
   1862   int user_arg = 0;
   1863 
   1864   if (arg)
   1865     {
   1866       char **argv;
   1867       int i;
   1868 
   1869       argv = gdb_buildargv (arg);
   1870       make_cleanup_freeargv (argv);
   1871       argc = 0;
   1872       for (i = 0; argv[i]; i++)
   1873 	{
   1874 	  unsigned int j;
   1875 
   1876 	  for (j = 0; j < strlen (argv[i]); j++)
   1877 	    argv[i][j] = tolower (argv[i][j]);
   1878 
   1879 	  if (no_filters < 0 && subset_compare (argv[i], "no-filters"))
   1880 	    no_filters = argc;
   1881 	  else
   1882 	    {
   1883 	      if (fulltrace_arg < 0 && subset_compare (argv[i], "full"))
   1884 		fulltrace_arg = argc;
   1885 	      else
   1886 		{
   1887 		  user_arg++;
   1888 		  arglen += strlen (argv[i]);
   1889 		}
   1890 	    }
   1891 	  argc++;
   1892 	}
   1893       arglen += user_arg;
   1894       if (fulltrace_arg >= 0 || no_filters >= 0)
   1895 	{
   1896 	  if (arglen > 0)
   1897 	    {
   1898 	      arg = xmalloc (arglen + 1);
   1899 	      make_cleanup (xfree, arg);
   1900 	      arg[0] = 0;
   1901 	      for (i = 0; i < argc; i++)
   1902 		{
   1903 		  if (i != fulltrace_arg && i != no_filters)
   1904 		    {
   1905 		      strcat (arg, argv[i]);
   1906 		      strcat (arg, " ");
   1907 		    }
   1908 		}
   1909 	    }
   1910 	  else
   1911 	    arg = NULL;
   1912 	}
   1913     }
   1914 
   1915   backtrace_command_1 (arg, fulltrace_arg >= 0 /* show_locals */,
   1916 		       no_filters >= 0 /* no frame-filters */, from_tty);
   1917 
   1918   do_cleanups (old_chain);
   1919 }
   1920 
   1921 static void
   1922 backtrace_full_command (char *arg, int from_tty)
   1923 {
   1924   backtrace_command_1 (arg, 1 /* show_locals */, 0, from_tty);
   1925 }
   1926 
   1927 
   1929 /* Iterate over the local variables of a block B, calling CB with
   1930    CB_DATA.  */
   1931 
   1932 static void
   1933 iterate_over_block_locals (const struct block *b,
   1934 			   iterate_over_block_arg_local_vars_cb cb,
   1935 			   void *cb_data)
   1936 {
   1937   struct block_iterator iter;
   1938   struct symbol *sym;
   1939 
   1940   ALL_BLOCK_SYMBOLS (b, iter, sym)
   1941     {
   1942       switch (SYMBOL_CLASS (sym))
   1943 	{
   1944 	case LOC_LOCAL:
   1945 	case LOC_REGISTER:
   1946 	case LOC_STATIC:
   1947 	case LOC_COMPUTED:
   1948 	  if (SYMBOL_IS_ARGUMENT (sym))
   1949 	    break;
   1950 	  if (SYMBOL_DOMAIN (sym) == COMMON_BLOCK_DOMAIN)
   1951 	    break;
   1952 	  (*cb) (SYMBOL_PRINT_NAME (sym), sym, cb_data);
   1953 	  break;
   1954 
   1955 	default:
   1956 	  /* Ignore symbols which are not locals.  */
   1957 	  break;
   1958 	}
   1959     }
   1960 }
   1961 
   1962 
   1963 /* Same, but print labels.  */
   1964 
   1965 #if 0
   1966 /* Commented out, as the code using this function has also been
   1967    commented out.  FIXME:brobecker/2009-01-13: Find out why the code
   1968    was commented out in the first place.  The discussion introducing
   1969    this change (2007-12-04: Support lexical blocks and function bodies
   1970    that occupy non-contiguous address ranges) did not explain why
   1971    this change was made.  */
   1972 static int
   1973 print_block_frame_labels (struct gdbarch *gdbarch, struct block *b,
   1974 			  int *have_default, struct ui_file *stream)
   1975 {
   1976   struct block_iterator iter;
   1977   struct symbol *sym;
   1978   int values_printed = 0;
   1979 
   1980   ALL_BLOCK_SYMBOLS (b, iter, sym)
   1981     {
   1982       if (strcmp (SYMBOL_LINKAGE_NAME (sym), "default") == 0)
   1983 	{
   1984 	  if (*have_default)
   1985 	    continue;
   1986 	  *have_default = 1;
   1987 	}
   1988       if (SYMBOL_CLASS (sym) == LOC_LABEL)
   1989 	{
   1990 	  struct symtab_and_line sal;
   1991 	  struct value_print_options opts;
   1992 
   1993 	  sal = find_pc_line (SYMBOL_VALUE_ADDRESS (sym), 0);
   1994 	  values_printed = 1;
   1995 	  fputs_filtered (SYMBOL_PRINT_NAME (sym), stream);
   1996 	  get_user_print_options (&opts);
   1997 	  if (opts.addressprint)
   1998 	    {
   1999 	      fprintf_filtered (stream, " ");
   2000 	      fputs_filtered (paddress (gdbarch, SYMBOL_VALUE_ADDRESS (sym)),
   2001 			      stream);
   2002 	    }
   2003 	  fprintf_filtered (stream, " in file %s, line %d\n",
   2004 			    sal.symtab->filename, sal.line);
   2005 	}
   2006     }
   2007 
   2008   return values_printed;
   2009 }
   2010 #endif
   2011 
   2012 /* Iterate over all the local variables in block B, including all its
   2013    superblocks, stopping when the top-level block is reached.  */
   2014 
   2015 void
   2016 iterate_over_block_local_vars (const struct block *block,
   2017 			       iterate_over_block_arg_local_vars_cb cb,
   2018 			       void *cb_data)
   2019 {
   2020   while (block)
   2021     {
   2022       iterate_over_block_locals (block, cb, cb_data);
   2023       /* After handling the function's top-level block, stop.  Don't
   2024 	 continue to its superblock, the block of per-file
   2025 	 symbols.  */
   2026       if (BLOCK_FUNCTION (block))
   2027 	break;
   2028       block = BLOCK_SUPERBLOCK (block);
   2029     }
   2030 }
   2031 
   2032 /* Data to be passed around in the calls to the locals and args
   2033    iterators.  */
   2034 
   2035 struct print_variable_and_value_data
   2036 {
   2037   struct frame_id frame_id;
   2038   int num_tabs;
   2039   struct ui_file *stream;
   2040   int values_printed;
   2041 };
   2042 
   2043 /* The callback for the locals and args iterators.  */
   2044 
   2045 static void
   2046 do_print_variable_and_value (const char *print_name,
   2047 			     struct symbol *sym,
   2048 			     void *cb_data)
   2049 {
   2050   struct print_variable_and_value_data *p = cb_data;
   2051   struct frame_info *frame;
   2052 
   2053   frame = frame_find_by_id (p->frame_id);
   2054   if (frame == NULL)
   2055     {
   2056       warning (_("Unable to restore previously selected frame."));
   2057       return;
   2058     }
   2059 
   2060   print_variable_and_value (print_name, sym, frame, p->stream, p->num_tabs);
   2061 
   2062   /* print_variable_and_value invalidates FRAME.  */
   2063   frame = NULL;
   2064 
   2065   p->values_printed = 1;
   2066 }
   2067 
   2068 /* Print all variables from the innermost up to the function block of FRAME.
   2069    Print them with values to STREAM indented by NUM_TABS.
   2070 
   2071    This function will invalidate FRAME.  */
   2072 
   2073 static void
   2074 print_frame_local_vars (struct frame_info *frame, int num_tabs,
   2075 			struct ui_file *stream)
   2076 {
   2077   struct print_variable_and_value_data cb_data;
   2078   const struct block *block;
   2079   CORE_ADDR pc;
   2080 
   2081   if (!get_frame_pc_if_available (frame, &pc))
   2082     {
   2083       fprintf_filtered (stream,
   2084 			_("PC unavailable, cannot determine locals.\n"));
   2085       return;
   2086     }
   2087 
   2088   block = get_frame_block (frame, 0);
   2089   if (block == 0)
   2090     {
   2091       fprintf_filtered (stream, "No symbol table info available.\n");
   2092       return;
   2093     }
   2094 
   2095   cb_data.frame_id = get_frame_id (frame);
   2096   cb_data.num_tabs = 4 * num_tabs;
   2097   cb_data.stream = stream;
   2098   cb_data.values_printed = 0;
   2099 
   2100   iterate_over_block_local_vars (block,
   2101 				 do_print_variable_and_value,
   2102 				 &cb_data);
   2103 
   2104   /* do_print_variable_and_value invalidates FRAME.  */
   2105   frame = NULL;
   2106 
   2107   if (!cb_data.values_printed)
   2108     fprintf_filtered (stream, _("No locals.\n"));
   2109 }
   2110 
   2111 void
   2112 locals_info (char *args, int from_tty)
   2113 {
   2114   print_frame_local_vars (get_selected_frame (_("No frame selected.")),
   2115 			  0, gdb_stdout);
   2116 }
   2117 
   2118 /* Iterate over all the argument variables in block B.
   2119 
   2120    Returns 1 if any argument was walked; 0 otherwise.  */
   2121 
   2122 void
   2123 iterate_over_block_arg_vars (const struct block *b,
   2124 			     iterate_over_block_arg_local_vars_cb cb,
   2125 			     void *cb_data)
   2126 {
   2127   struct block_iterator iter;
   2128   struct symbol *sym, *sym2;
   2129 
   2130   ALL_BLOCK_SYMBOLS (b, iter, sym)
   2131     {
   2132       /* Don't worry about things which aren't arguments.  */
   2133       if (SYMBOL_IS_ARGUMENT (sym))
   2134 	{
   2135 	  /* We have to look up the symbol because arguments can have
   2136 	     two entries (one a parameter, one a local) and the one we
   2137 	     want is the local, which lookup_symbol will find for us.
   2138 	     This includes gcc1 (not gcc2) on the sparc when passing a
   2139 	     small structure and gcc2 when the argument type is float
   2140 	     and it is passed as a double and converted to float by
   2141 	     the prologue (in the latter case the type of the LOC_ARG
   2142 	     symbol is double and the type of the LOC_LOCAL symbol is
   2143 	     float).  There are also LOC_ARG/LOC_REGISTER pairs which
   2144 	     are not combined in symbol-reading.  */
   2145 
   2146 	  sym2 = lookup_symbol (SYMBOL_LINKAGE_NAME (sym),
   2147 				b, VAR_DOMAIN, NULL);
   2148 	  (*cb) (SYMBOL_PRINT_NAME (sym), sym2, cb_data);
   2149 	}
   2150     }
   2151 }
   2152 
   2153 /* Print all argument variables of the function of FRAME.
   2154    Print them with values to STREAM.
   2155 
   2156    This function will invalidate FRAME.  */
   2157 
   2158 static void
   2159 print_frame_arg_vars (struct frame_info *frame, struct ui_file *stream)
   2160 {
   2161   struct print_variable_and_value_data cb_data;
   2162   struct symbol *func;
   2163   CORE_ADDR pc;
   2164 
   2165   if (!get_frame_pc_if_available (frame, &pc))
   2166     {
   2167       fprintf_filtered (stream, _("PC unavailable, cannot determine args.\n"));
   2168       return;
   2169     }
   2170 
   2171   func = get_frame_function (frame);
   2172   if (func == NULL)
   2173     {
   2174       fprintf_filtered (stream, _("No symbol table info available.\n"));
   2175       return;
   2176     }
   2177 
   2178   cb_data.frame_id = get_frame_id (frame);
   2179   cb_data.num_tabs = 0;
   2180   cb_data.stream = gdb_stdout;
   2181   cb_data.values_printed = 0;
   2182 
   2183   iterate_over_block_arg_vars (SYMBOL_BLOCK_VALUE (func),
   2184 			       do_print_variable_and_value, &cb_data);
   2185 
   2186   /* do_print_variable_and_value invalidates FRAME.  */
   2187   frame = NULL;
   2188 
   2189   if (!cb_data.values_printed)
   2190     fprintf_filtered (stream, _("No arguments.\n"));
   2191 }
   2192 
   2193 void
   2194 args_info (char *ignore, int from_tty)
   2195 {
   2196   print_frame_arg_vars (get_selected_frame (_("No frame selected.")),
   2197 			gdb_stdout);
   2198 }
   2199 
   2200 
   2201 static void
   2202 args_plus_locals_info (char *ignore, int from_tty)
   2203 {
   2204   args_info (ignore, from_tty);
   2205   locals_info (ignore, from_tty);
   2206 }
   2207 
   2208 
   2210 /* Select frame FRAME.  Also print the stack frame and show the source
   2211    if this is the tui version.  */
   2212 static void
   2213 select_and_print_frame (struct frame_info *frame)
   2214 {
   2215   select_frame (frame);
   2216   if (frame)
   2217     print_stack_frame (frame, 1, SRC_AND_LOC, 1);
   2218 }
   2219 
   2220 /* Return the symbol-block in which the selected frame is executing.
   2222    Can return zero under various legitimate circumstances.
   2223 
   2224    If ADDR_IN_BLOCK is non-zero, set *ADDR_IN_BLOCK to the relevant
   2225    code address within the block returned.  We use this to decide
   2226    which macros are in scope.  */
   2227 
   2228 const struct block *
   2229 get_selected_block (CORE_ADDR *addr_in_block)
   2230 {
   2231   if (!has_stack_frames ())
   2232     return 0;
   2233 
   2234   return get_frame_block (get_selected_frame (NULL), addr_in_block);
   2235 }
   2236 
   2237 /* Find a frame a certain number of levels away from FRAME.
   2238    LEVEL_OFFSET_PTR points to an int containing the number of levels.
   2239    Positive means go to earlier frames (up); negative, the reverse.
   2240    The int that contains the number of levels is counted toward
   2241    zero as the frames for those levels are found.
   2242    If the top or bottom frame is reached, that frame is returned,
   2243    but the final value of *LEVEL_OFFSET_PTR is nonzero and indicates
   2244    how much farther the original request asked to go.  */
   2245 
   2246 struct frame_info *
   2247 find_relative_frame (struct frame_info *frame, int *level_offset_ptr)
   2248 {
   2249   /* Going up is simple: just call get_prev_frame enough times or
   2250      until the initial frame is reached.  */
   2251   while (*level_offset_ptr > 0)
   2252     {
   2253       struct frame_info *prev = get_prev_frame (frame);
   2254 
   2255       if (!prev)
   2256 	break;
   2257       (*level_offset_ptr)--;
   2258       frame = prev;
   2259     }
   2260 
   2261   /* Going down is just as simple.  */
   2262   while (*level_offset_ptr < 0)
   2263     {
   2264       struct frame_info *next = get_next_frame (frame);
   2265 
   2266       if (!next)
   2267 	break;
   2268       (*level_offset_ptr)++;
   2269       frame = next;
   2270     }
   2271 
   2272   return frame;
   2273 }
   2274 
   2275 /* The "select_frame" command.  With no argument this is a NOP.
   2276    Select the frame at level LEVEL_EXP if it is a valid level.
   2277    Otherwise, treat LEVEL_EXP as an address expression and select it.
   2278 
   2279    See parse_frame_specification for more info on proper frame
   2280    expressions.  */
   2281 
   2282 void
   2283 select_frame_command (char *level_exp, int from_tty)
   2284 {
   2285   select_frame (parse_frame_specification_1 (level_exp, "No stack.", NULL));
   2286 }
   2287 
   2288 /* The "frame" command.  With no argument, print the selected frame
   2289    briefly.  With an argument, behave like select_frame and then print
   2290    the selected frame.  */
   2291 
   2292 static void
   2293 frame_command (char *level_exp, int from_tty)
   2294 {
   2295   select_frame_command (level_exp, from_tty);
   2296   print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
   2297 }
   2298 
   2299 /* The XDB Compatibility command to print the current frame.  */
   2300 
   2301 static void
   2302 current_frame_command (char *level_exp, int from_tty)
   2303 {
   2304   print_stack_frame (get_selected_frame (_("No stack.")), 1, SRC_AND_LOC, 1);
   2305 }
   2306 
   2307 /* Select the frame up one or COUNT_EXP stack levels from the
   2308    previously selected frame, and print it briefly.  */
   2309 
   2310 static void
   2311 up_silently_base (const char *count_exp)
   2312 {
   2313   struct frame_info *frame;
   2314   int count = 1;
   2315 
   2316   if (count_exp)
   2317     count = parse_and_eval_long (count_exp);
   2318 
   2319   frame = find_relative_frame (get_selected_frame ("No stack."), &count);
   2320   if (count != 0 && count_exp == NULL)
   2321     error (_("Initial frame selected; you cannot go up."));
   2322   select_frame (frame);
   2323 }
   2324 
   2325 static void
   2326 up_silently_command (char *count_exp, int from_tty)
   2327 {
   2328   up_silently_base (count_exp);
   2329 }
   2330 
   2331 static void
   2332 up_command (char *count_exp, int from_tty)
   2333 {
   2334   up_silently_base (count_exp);
   2335   print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
   2336 }
   2337 
   2338 /* Select the frame down one or COUNT_EXP stack levels from the previously
   2339    selected frame, and print it briefly.  */
   2340 
   2341 static void
   2342 down_silently_base (const char *count_exp)
   2343 {
   2344   struct frame_info *frame;
   2345   int count = -1;
   2346 
   2347   if (count_exp)
   2348     count = -parse_and_eval_long (count_exp);
   2349 
   2350   frame = find_relative_frame (get_selected_frame ("No stack."), &count);
   2351   if (count != 0 && count_exp == NULL)
   2352     {
   2353       /* We only do this if COUNT_EXP is not specified.  That way
   2354          "down" means to really go down (and let me know if that is
   2355          impossible), but "down 9999" can be used to mean go all the
   2356          way down without getting an error.  */
   2357 
   2358       error (_("Bottom (innermost) frame selected; you cannot go down."));
   2359     }
   2360 
   2361   select_frame (frame);
   2362 }
   2363 
   2364 static void
   2365 down_silently_command (char *count_exp, int from_tty)
   2366 {
   2367   down_silently_base (count_exp);
   2368 }
   2369 
   2370 static void
   2371 down_command (char *count_exp, int from_tty)
   2372 {
   2373   down_silently_base (count_exp);
   2374   print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
   2375 }
   2376 
   2377 
   2379 void
   2380 return_command (char *retval_exp, int from_tty)
   2381 {
   2382   /* Initialize it just to avoid a GCC false warning.  */
   2383   enum return_value_convention rv_conv = RETURN_VALUE_STRUCT_CONVENTION;
   2384   struct frame_info *thisframe;
   2385   struct gdbarch *gdbarch;
   2386   struct symbol *thisfun;
   2387   struct value *return_value = NULL;
   2388   struct value *function = NULL;
   2389   const char *query_prefix = "";
   2390 
   2391   thisframe = get_selected_frame ("No selected frame.");
   2392   thisfun = get_frame_function (thisframe);
   2393   gdbarch = get_frame_arch (thisframe);
   2394 
   2395   if (get_frame_type (get_current_frame ()) == INLINE_FRAME)
   2396     error (_("Can not force return from an inlined function."));
   2397 
   2398   /* Compute the return value.  If the computation triggers an error,
   2399      let it bail.  If the return type can't be handled, set
   2400      RETURN_VALUE to NULL, and QUERY_PREFIX to an informational
   2401      message.  */
   2402   if (retval_exp)
   2403     {
   2404       struct expression *retval_expr = parse_expression (retval_exp);
   2405       struct cleanup *old_chain = make_cleanup (xfree, retval_expr);
   2406       struct type *return_type = NULL;
   2407 
   2408       /* Compute the return value.  Should the computation fail, this
   2409          call throws an error.  */
   2410       return_value = evaluate_expression (retval_expr);
   2411 
   2412       /* Cast return value to the return type of the function.  Should
   2413          the cast fail, this call throws an error.  */
   2414       if (thisfun != NULL)
   2415 	return_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (thisfun));
   2416       if (return_type == NULL)
   2417       	{
   2418 	  if (retval_expr->elts[0].opcode != UNOP_CAST
   2419 	      && retval_expr->elts[0].opcode != UNOP_CAST_TYPE)
   2420 	    error (_("Return value type not available for selected "
   2421 		     "stack frame.\n"
   2422 		     "Please use an explicit cast of the value to return."));
   2423 	  return_type = value_type (return_value);
   2424 	}
   2425       do_cleanups (old_chain);
   2426       CHECK_TYPEDEF (return_type);
   2427       return_value = value_cast (return_type, return_value);
   2428 
   2429       /* Make sure the value is fully evaluated.  It may live in the
   2430          stack frame we're about to pop.  */
   2431       if (value_lazy (return_value))
   2432 	value_fetch_lazy (return_value);
   2433 
   2434       if (thisfun != NULL)
   2435 	function = read_var_value (thisfun, thisframe);
   2436 
   2437       rv_conv = RETURN_VALUE_REGISTER_CONVENTION;
   2438       if (TYPE_CODE (return_type) == TYPE_CODE_VOID)
   2439 	/* If the return-type is "void", don't try to find the
   2440            return-value's location.  However, do still evaluate the
   2441            return expression so that, even when the expression result
   2442            is discarded, side effects such as "return i++" still
   2443            occur.  */
   2444 	return_value = NULL;
   2445       else if (thisfun != NULL)
   2446 	{
   2447 	  rv_conv = struct_return_convention (gdbarch, function, return_type);
   2448 	  if (rv_conv == RETURN_VALUE_STRUCT_CONVENTION
   2449 	      || rv_conv == RETURN_VALUE_ABI_RETURNS_ADDRESS)
   2450 	    {
   2451 	      query_prefix = "The location at which to store the "
   2452 		"function's return value is unknown.\n"
   2453 		"If you continue, the return value "
   2454 		"that you specified will be ignored.\n";
   2455 	      return_value = NULL;
   2456 	    }
   2457 	}
   2458     }
   2459 
   2460   /* Does an interactive user really want to do this?  Include
   2461      information, such as how well GDB can handle the return value, in
   2462      the query message.  */
   2463   if (from_tty)
   2464     {
   2465       int confirmed;
   2466 
   2467       if (thisfun == NULL)
   2468 	confirmed = query (_("%sMake selected stack frame return now? "),
   2469 			   query_prefix);
   2470       else
   2471 	confirmed = query (_("%sMake %s return now? "), query_prefix,
   2472 			   SYMBOL_PRINT_NAME (thisfun));
   2473       if (!confirmed)
   2474 	error (_("Not confirmed"));
   2475     }
   2476 
   2477   /* Discard the selected frame and all frames inner-to it.  */
   2478   frame_pop (get_selected_frame (NULL));
   2479 
   2480   /* Store RETURN_VALUE in the just-returned register set.  */
   2481   if (return_value != NULL)
   2482     {
   2483       struct type *return_type = value_type (return_value);
   2484       struct gdbarch *gdbarch = get_regcache_arch (get_current_regcache ());
   2485 
   2486       gdb_assert (rv_conv != RETURN_VALUE_STRUCT_CONVENTION
   2487 		  && rv_conv != RETURN_VALUE_ABI_RETURNS_ADDRESS);
   2488       gdbarch_return_value (gdbarch, function, return_type,
   2489 			    get_current_regcache (), NULL /*read*/,
   2490 			    value_contents (return_value) /*write*/);
   2491     }
   2492 
   2493   /* If we are at the end of a call dummy now, pop the dummy frame
   2494      too.  */
   2495   if (get_frame_type (get_current_frame ()) == DUMMY_FRAME)
   2496     frame_pop (get_current_frame ());
   2497 
   2498   /* If interactive, print the frame that is now current.  */
   2499   if (from_tty)
   2500     frame_command ("0", 1);
   2501   else
   2502     select_frame_command ("0", 0);
   2503 }
   2504 
   2505 /* Sets the scope to input function name, provided that the function
   2506    is within the current stack frame.  */
   2507 
   2508 struct function_bounds
   2509 {
   2510   CORE_ADDR low, high;
   2511 };
   2512 
   2513 static void
   2514 func_command (char *arg, int from_tty)
   2515 {
   2516   struct frame_info *frame;
   2517   int found = 0;
   2518   struct symtabs_and_lines sals;
   2519   int i;
   2520   int level = 1;
   2521   struct function_bounds *func_bounds = NULL;
   2522   struct cleanup *cleanups;
   2523 
   2524   if (arg != NULL)
   2525     return;
   2526 
   2527   frame = parse_frame_specification ("0");
   2528   sals = decode_line_with_current_source (arg, DECODE_LINE_FUNFIRSTLINE);
   2529   cleanups = make_cleanup (xfree, sals.sals);
   2530   func_bounds = (struct function_bounds *) xmalloc (
   2531 			      sizeof (struct function_bounds) * sals.nelts);
   2532   make_cleanup (xfree, func_bounds);
   2533   for (i = 0; (i < sals.nelts && !found); i++)
   2534     {
   2535       if (sals.sals[i].pspace != current_program_space)
   2536 	func_bounds[i].low = func_bounds[i].high = 0;
   2537       else if (sals.sals[i].pc == 0
   2538 	       || find_pc_partial_function (sals.sals[i].pc, NULL,
   2539 					    &func_bounds[i].low,
   2540 					    &func_bounds[i].high) == 0)
   2541 	{
   2542 	  func_bounds[i].low = func_bounds[i].high = 0;
   2543 	}
   2544     }
   2545 
   2546   do
   2547     {
   2548       for (i = 0; (i < sals.nelts && !found); i++)
   2549 	found = (get_frame_pc (frame) >= func_bounds[i].low
   2550 		 && get_frame_pc (frame) < func_bounds[i].high);
   2551       if (!found)
   2552 	{
   2553 	  level = 1;
   2554 	  frame = find_relative_frame (frame, &level);
   2555 	}
   2556     }
   2557   while (!found && level == 0);
   2558 
   2559   do_cleanups (cleanups);
   2560 
   2561   if (!found)
   2562     printf_filtered (_("'%s' not within current stack frame.\n"), arg);
   2563   else if (frame != get_selected_frame (NULL))
   2564     select_and_print_frame (frame);
   2565 }
   2566 
   2567 /* Gets the language of the current frame.  */
   2568 
   2569 enum language
   2570 get_frame_language (void)
   2571 {
   2572   struct frame_info *frame = deprecated_safe_get_selected_frame ();
   2573 
   2574   if (frame)
   2575     {
   2576       volatile struct gdb_exception ex;
   2577       CORE_ADDR pc = 0;
   2578 
   2579       /* We determine the current frame language by looking up its
   2580          associated symtab.  To retrieve this symtab, we use the frame
   2581          PC.  However we cannot use the frame PC as is, because it
   2582          usually points to the instruction following the "call", which
   2583          is sometimes the first instruction of another function.  So
   2584          we rely on get_frame_address_in_block(), it provides us with
   2585          a PC that is guaranteed to be inside the frame's code
   2586          block.  */
   2587 
   2588       TRY_CATCH (ex, RETURN_MASK_ERROR)
   2589 	{
   2590 	  pc = get_frame_address_in_block (frame);
   2591 	}
   2592       if (ex.reason < 0)
   2593 	{
   2594 	  if (ex.error != NOT_AVAILABLE_ERROR)
   2595 	    throw_exception (ex);
   2596 	}
   2597       else
   2598 	{
   2599 	  struct compunit_symtab *cust = find_pc_compunit_symtab (pc);
   2600 
   2601 	  if (cust != NULL)
   2602 	    return compunit_language (cust);
   2603 	}
   2604     }
   2605 
   2606   return language_unknown;
   2607 }
   2608 
   2609 
   2611 /* Provide a prototype to silence -Wmissing-prototypes.  */
   2612 void _initialize_stack (void);
   2613 
   2614 void
   2615 _initialize_stack (void)
   2616 {
   2617   add_com ("return", class_stack, return_command, _("\
   2618 Make selected stack frame return to its caller.\n\
   2619 Control remains in the debugger, but when you continue\n\
   2620 execution will resume in the frame above the one now selected.\n\
   2621 If an argument is given, it is an expression for the value to return."));
   2622 
   2623   add_com ("up", class_stack, up_command, _("\
   2624 Select and print stack frame that called this one.\n\
   2625 An argument says how many frames up to go."));
   2626   add_com ("up-silently", class_support, up_silently_command, _("\
   2627 Same as the `up' command, but does not print anything.\n\
   2628 This is useful in command scripts."));
   2629 
   2630   add_com ("down", class_stack, down_command, _("\
   2631 Select and print stack frame called by this one.\n\
   2632 An argument says how many frames down to go."));
   2633   add_com_alias ("do", "down", class_stack, 1);
   2634   add_com_alias ("dow", "down", class_stack, 1);
   2635   add_com ("down-silently", class_support, down_silently_command, _("\
   2636 Same as the `down' command, but does not print anything.\n\
   2637 This is useful in command scripts."));
   2638 
   2639   add_com ("frame", class_stack, frame_command, _("\
   2640 Select and print a stack frame.\nWith no argument, \
   2641 print the selected stack frame.  (See also \"info frame\").\n\
   2642 An argument specifies the frame to select.\n\
   2643 It can be a stack frame number or the address of the frame.\n\
   2644 With argument, nothing is printed if input is coming from\n\
   2645 a command file or a user-defined command."));
   2646 
   2647   add_com_alias ("f", "frame", class_stack, 1);
   2648 
   2649   if (xdb_commands)
   2650     {
   2651       add_com ("L", class_stack, current_frame_command,
   2652 	       _("Print the current stack frame.\n"));
   2653       add_com_alias ("V", "frame", class_stack, 1);
   2654     }
   2655   add_com ("select-frame", class_stack, select_frame_command, _("\
   2656 Select a stack frame without printing anything.\n\
   2657 An argument specifies the frame to select.\n\
   2658 It can be a stack frame number or the address of the frame.\n"));
   2659 
   2660   add_com ("backtrace", class_stack, backtrace_command, _("\
   2661 Print backtrace of all stack frames, or innermost COUNT frames.\n\
   2662 With a negative argument, print outermost -COUNT frames.\nUse of the \
   2663 'full' qualifier also prints the values of the local variables.\n\
   2664 Use of the 'no-filters' qualifier prohibits frame filters from executing\n\
   2665 on this backtrace.\n"));
   2666   add_com_alias ("bt", "backtrace", class_stack, 0);
   2667   if (xdb_commands)
   2668     {
   2669       add_com_alias ("t", "backtrace", class_stack, 0);
   2670       add_com ("T", class_stack, backtrace_full_command, _("\
   2671 Print backtrace of all stack frames, or innermost COUNT frames\n\
   2672 and the values of the local variables.\n\
   2673 With a negative argument, print outermost -COUNT frames.\n\
   2674 Usage: T <count>\n"));
   2675     }
   2676 
   2677   add_com_alias ("where", "backtrace", class_alias, 0);
   2678   add_info ("stack", backtrace_command,
   2679 	    _("Backtrace of the stack, or innermost COUNT frames."));
   2680   add_info_alias ("s", "stack", 1);
   2681   add_info ("frame", frame_info,
   2682 	    _("All about selected stack frame, or frame at ADDR."));
   2683   add_info_alias ("f", "frame", 1);
   2684   add_info ("locals", locals_info,
   2685 	    _("Local variables of current stack frame."));
   2686   add_info ("args", args_info,
   2687 	    _("Argument variables of current stack frame."));
   2688   if (xdb_commands)
   2689     add_com ("l", class_info, args_plus_locals_info,
   2690 	     _("Argument and local variables of current stack frame."));
   2691 
   2692   if (dbx_commands)
   2693     add_com ("func", class_stack, func_command, _("\
   2694 Select the stack frame that contains <func>.\n\
   2695 Usage: func <name>\n"));
   2696 
   2697   add_setshow_enum_cmd ("frame-arguments", class_stack,
   2698 			print_frame_arguments_choices, &print_frame_arguments,
   2699 			_("Set printing of non-scalar frame arguments"),
   2700 			_("Show printing of non-scalar frame arguments"),
   2701 			NULL, NULL, NULL, &setprintlist, &showprintlist);
   2702 
   2703   add_setshow_boolean_cmd ("frame-arguments", no_class,
   2704 			   &print_raw_frame_arguments, _("\
   2705 Set whether to print frame arguments in raw form."), _("\
   2706 Show whether to print frame arguments in raw form."), _("\
   2707 If set, frame arguments are printed in raw form, bypassing any\n\
   2708 pretty-printers for that value."),
   2709 			   NULL, NULL,
   2710 			   &setprintrawlist, &showprintrawlist);
   2711 
   2712   add_setshow_auto_boolean_cmd ("disassemble-next-line", class_stack,
   2713 			        &disassemble_next_line, _("\
   2714 Set whether to disassemble next source line or insn when execution stops."),
   2715 				_("\
   2716 Show whether to disassemble next source line or insn when execution stops."),
   2717 				_("\
   2718 If ON, GDB will display disassembly of the next source line, in addition\n\
   2719 to displaying the source line itself.  If the next source line cannot\n\
   2720 be displayed (e.g., source is unavailable or there's no line info), GDB\n\
   2721 will display disassembly of next instruction instead of showing the\n\
   2722 source line.\n\
   2723 If AUTO, display disassembly of next instruction only if the source line\n\
   2724 cannot be displayed.\n\
   2725 If OFF (which is the default), never display the disassembly of the next\n\
   2726 source line."),
   2727 			        NULL,
   2728 			        show_disassemble_next_line,
   2729 			        &setlist, &showlist);
   2730   disassemble_next_line = AUTO_BOOLEAN_FALSE;
   2731 
   2732   add_setshow_enum_cmd ("entry-values", class_stack,
   2733 			print_entry_values_choices, &print_entry_values,
   2734 			_("Set printing of function arguments at function "
   2735 			  "entry"),
   2736 			_("Show printing of function arguments at function "
   2737 			  "entry"),
   2738 			_("\
   2739 GDB can sometimes determine the values of function arguments at entry,\n\
   2740 in addition to their current values.  This option tells GDB whether\n\
   2741 to print the current value, the value at entry (marked as val@entry),\n\
   2742 or both.  Note that one or both of these values may be <optimized out>."),
   2743 			NULL, NULL, &setprintlist, &showprintlist);
   2744 }
   2745