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HACKS revision 1.52
      1 # $NetBSD: HACKS,v 1.52 2005/12/13 05:56:23 jmc Exp $
      2 #
      3 # This file is intended to document workarounds for currently unsolved
      4 # (mostly) compiler bugs.
      5 #
      6 # Format:
      7 #   hack		title
      8 #   cdate		creation date
      9 #   mdate		mod date
     10 #   who			responsible developer
     11 #   port		...
     12 #  	  affected ports, space separated, if not "all"
     13 #   file		affected file : revision : line from : line to
     14 #  	  affected files and revision and line numbers describing hack
     15 #  	  multiple lines if necessary.
     16 #   pr			NNNN ...
     17 #  	  problem reports this hack works around, if known. Space
     18 #  	  separated.
     19 #   regress		src/regress/directory/where/test/found
     20 #  	  regression test directories, if available.
     21 #   descr
     22 #  	  insert short informal description (multi-line). (Longer ones
     23 #  	  should be in the PR database. More formal descriptions might
     24 #  	  be in the regress tree. See above).
     25 #   kcah
     26 #  	  closing bracket.
     27 #
     28 # this is a comment.
     29 
     30 hack	netstat ieee1394 address printing.
     31 mdate	14 Nov 2000
     32 who	matt
     33 file	lib/libc/net/getnameinfo.c	: 1.32 : 497 : 503
     34 descr
     35 	Because the current implementation of IP over IEEE1394, the
     36 	fw device address contains more than just the IEEE1394 EUI-64.
     37 	So when printing out IEEE1394 addresses, ignore the extra stuff.
     38 kcah
     39 
     40 hack	xterm vs. libterm
     41 mdate	01 Aug 2000
     42 who	jdc
     43 file	xsrc/xc/programs/xterm/main.c	: 1.2 : 3609 : 3614
     44 pr	10383
     45 descr
     46 	In order to extend the termcap string over 1023 bytes, a ZZ entry was
     47 	introduced to point to a memory location containing the full entry.
     48 	Without this hack, xterm will export a termcap containing the ZZ
     49 	entry, which will then be ignored by libterm.  As xterm modifies the
     50 	exported termcap, this would cause those modifications to be ignored.
     51 kcah
     52 
     53 hack	wi-at-big-endian-bus
     54 cdate	15 Mar 2002
     55 who	martin
     56 file	dev/ic/wireg.h
     57 descr	Add an option to access the underlying bus in big endian byte order
     58 	to work around deficiencies in bus_space_{read,write}_* macros.
     59 	Those don't allow the implementation of a proper pcmcia bus space
     60 	tag.
     61 kcah
     62 
     63 hack	specific knowledge of colours in curses code
     64 cdate	Sun Apr  6 11:05:24 BST 2003
     65 who	jdc
     66 file	lib/libcurses/color.c : r1.24
     67 descr
     68 	Swap red/blue and yellow/cyan colours for COLOR_OTHER.
     69 	Fix is to enhance libtermcap to understand terminfo-style % sequences.
     70 	See also:
     71 	    http://mail-index.NetBSD.org/tech-userlevel/2003/04/06/0000.html
     72 kcah
     73 
     74 hack	Compensation for differing types of LINUX_USRSTACK and USRSTACK
     75 cdate	21 Aug 2003
     76 who	he
     77 file	sys/miscfs/procfs/procfs_linux.c : 1.14
     78 descr
     79 	Not all ports have LINUX_USRSTACK and/or USRSTACK defined as
     80 	literals/constants, but refer to variables of a type which is
     81 	not "unsigned long", causing compilation of procfs_linux.c to
     82 	fail with "makes integer from pointer without a cast".  This
     83 	is observed on e.g. the sun3 port.  Ideally the "types" for
     84 	symbols should be consistent across all ports.
     85 kcah
     86 
     87 hack	GCC2 isn't C99
     88 cdate	5 December 2003
     89 who	mrg
     90 file	gnu/dist/binutils/ld/ldlex.c: r1.2
     91 descr
     92 	ldlex.c is generated from ldlex.l and we get macro redefinition
     93 	errors from it if __STDC_VERSION__ is not C99 compliant.  This
     94 	hack forces NetBSD 1.6 and later systems to also include <stdint.h>
     95 	to get the relevant definitions.  This hack should be backed out
     96 	when all platforms have switched away from GCC2.
     97 kcah
     98 
     99 hack	gcc-strict-aliasing
    100 cdate	6 August 2004
    101 who	junyoung
    102 pr	26516
    103 file	src/usr.sbin/racoon/racoon/Makefile : 1.21
    104 descr
    105 	GCC issues a warning "dereferencing type-punned pointer will break
    106 	strict-aliasing rules" when compiling
    107 	crypto/dist/kame/racoon/crypto/openssl.c with -O[23s]. Note that this
    108 	is due to use of type casting in a non-standard way in the code and
    109 	not a compiler bug. Once a new release of KAME with a proper fix
    110 	applied is imported this should be backed out.
    111 kcah
    112 
    113 
    114 port	vax
    115 
    116 	hack	gcc 2.95/vax doesn't like abort being used as function pointer
    117 	cdate	Tue Dec 13 05:54:50 GMT 2005
    118 	who	jmc
    119 	file	lib/libc/rpc/svc_vc.c 1.15
    120 	descr
    121 		Provide a local definition for abort which doesn't include
    122 		the noreturn attribute which trips up gcc 2.95 on vax.
    123 	
    124 	hack	gcc 2.95/vax doesn't have stdbool.h and gettext needs it
    125 	cdate	Mon May  9 12:16:22 CDT 2005
    126 	who	jmc
    127 	file	gnu/usr.bin/gettext/Makefile.inc.prog 1.5
    128 		gnu/usr.bin/gettext/libgrep/Makefile 1.3
    129 		gnu/usr.bin/gettext/libnlspr/Makefile 1.5
    130 		gnu/usr.bin/gettext/libnlsut/Makefile 1.3   
    131 	descr
    132 		The latest gettext assumes a C99 environment or at least
    133 		configure checks to work around this. As we don't use configure
    134 		provide a stdbool.h for vax builds locally in directories from
    135 		the template provided by the gettext code.
    136 	
    137 	hack	gcc 2.95/vax can't handle __used__ in mcount.c
    138 	cdate	Fri May  6 14:30:53 CDT 2005
    139 	who	jmc
    140 	file	src/lib/libc/gmon/mcount.c 1.17
    141 	descr
    142                 Recent changes to mark this as __used__ to prevent optimization
    143                 away on sparc64 don't work on 2.95 vax. Ifdef'd back in the
    144                 old __unused__ if on vax.
    145 	
    146 	hack	gcc 2.95/vax cannot handle __builtin_ffs()
    147 	cdate	Fri Aug 23 21:31:15 CEST 2002
    148 	who	ragge
    149 	file	sys/lib/libkern/libkern.h : 1.42
    150 	descr
    151 		__builtin_ffs() is ifdef'd away if __vax__. Matt Thomas has
    152 		added this feature to GCC 3 so it can be removed when switching.
    153 	
    154 
    155 	hack	gcc-vax-libbz2
    156 	mdate	27 Jun 2002
    157 	who	thorpej
    158 	file	lib/libbz2/Makefile
    159 	descr
    160 		libbz2 is mis-compiled with optimization with GCC 2.95.3
    161 		on VAX.  -O0 works around this problem.
    162 	kcah
    163 
    164 	hack	gawk
    165 	mdate	8 Nov 2003
    166 	who	ragge
    167 	file	gnu/usr.bin/gawk/Makefile
    168 	descr
    169 		gawk is mis-compiled with optimization with GCC 2.95.3
    170 		on VAX.  -O0 works around this problem.
    171 	kcah
    172 
    173 	hack	vax Toolchain bug
    174 	cdate	28 Mar 2003
    175 	who	he
    176 	file	sys/arch/vax/vax/intvec.S : 1.5
    177 	descr
    178 		Workaround for PR toolchain/20924.  The assembler apparently
    179 		tries to range-check byte offsets when it doesn't have
    180 		sufficient information to make that decision.
    181 		Workaround uses `brw' instead of `brb' instruction.
    182 	kcah
    183 
    184 	hack	vax gcc 2.95.3 -Wuninitialized workarounds
    185 	cdate	6 Nov 2003
    186 	who	he
    187 	file	sys/dev/bi/if_ni.c : 1.22
    188 	file	sys/arch/vax/vax/ctu.c : 1.20
    189 	descr
    190 		Workaround for gcc 2.95.3 failing to detect that certain
    191 		variables will be initialized; so that this code compiles
    192 		with -Wuninitialized.  Should be reviewed and possibly
    193 		reverted when gcc 3.3.2 is ready for vax.
    194 	kcah
    195 
    196 	hack	vax gcc 2.95.3 structure initialization
    197 	cdat	13 May 2004
    198 	who	cl
    199 	file	sys/miscfs/kernfs/kernfs_vnops.c : 1.104
    200 	descr
    201 		Workaround for gcc 2.95.3 failing to initialize structures
    202 		and/or unions inside structures using nested designators.
    203 		Should be reverted when gcc >=3.3.3 is ready for vax.
    204 	kcah
    205 
    206 	hack	vax gcc 2.95.3 needs -I. to build nslexer.c
    207 	cdat	6 Jun 2004
    208 	who	mhitch
    209 	file	lib/libc/arch/vax/Makefile.inc : 1.6
    210 	descr
    211 		It appears necessary to add -I. to CPPFLAGS when building
    212 		nslesxer.c.  This may be caused by gcc 2.95.3 being used.
    213 		Should be reverted when a newer gcc is ready for vax.
    214 	kcah
    215 
    216 	hack	vax gcc 2.95.3 doesn't understand "-std=c99"
    217 	cdat	5 April 2005
    218 	who	tron
    219 	file	src/share/mk/bsd.sys.mk
    220 	descr
    221 		We cannot use "-std=c99" for compiler warning level 4 and above
    222 		because gcc 2.95.3 doesn't support that option.
    223 	kcah
    224 
    225 port	sparc64
    226 
    227 	hack	binutil-2.11-sparc64-pltrela
    228 	mdate	14 Aug 2001
    229 	who	eeh
    230 	file	libexec/ld.elf_so/arch/sparc64/mdreloc.c
    231 	descr
    232 		The first four PLT entries are reserved.  There is some
    233 		disagreement whether they should have associated relocation
    234 		entries.  Both the SPARC 32-bit and 64-bit ELF specifications
    235 		say that they should have relocation entries, but the 32-bit
    236 		SPARC binutils do not generate them, and now the 64-bit SPARC
    237 		binutils have stopped generating them too.
    238 
    239 		To provide binary compatibility, we will check the first entry,
    240 		if it is reserved it should not be of the type JMP_SLOT.  If it
    241 		is JMP_SLOT, then the 4 reserved entries were not generated and
    242 		our index is 4 entries too far, so we frob the rela pointer.
    243 	kcah
    244 
    245 
    246 port	arm
    247 
    248 	hack	gcc-unsigned-compare
    249 	cdate	09 Mar 2002
    250 	mdate	18 Mar 2002
    251 	who	bjh21
    252 	file	dist/bind/lib/nameser/ns_parse.c : 1.3
    253 	file	dist/dhcp/minires/ns_parse.c : 1.3
    254 	file	dist/dhcp/omapip/result.c : 1.2
    255 	file	dist/dhcp/server/failover.c : 1.3
    256 	file	gnu/dist/gawk/eval.c : 1.4
    257 	file	gnu/dist/toolchain/bfd/bfd.c : 1.2
    258 	file	gnu/dist/toolchain/bfd/format.c : 1.2
    259 	file	gnu/dist/toolchain/gdb/target.c : 1.2
    260 	file	sys/kern/vfs_subr.c : 1.172
    261 	descr	When checking that a potentially-unsigned enum is >= 0, assign
    262 		it to an int first.  This is necessary to avoid "comparison is
    263 		always true" warnings with -fshort-enums.  Casting to an int
    264 		really should be enough, but turns out not to be.
    265 	kcah
    266 
    267 	hack	gcc 3.3.2/arm sys/kern/uipc_socket.c
    268 	cdate	Tue Oct 28 18:02:16 GMT 2003
    269 	who	skrll
    270 	pr	23044
    271 	file	sys/arch/arm/conf/Makefile.arm : 1.19
    272 	descr
    273 		Performing a build.sh tools on a CATS with NFS mounted 
    274 		obj and src directories results in "panic: receive 1"
    275 		The hack is to compile sys/kern/uipc_socket.c with
    276 		-fno-strict-aliasing
    277 	kcah
    278 
    279 
    280 port	pc532
    281 
    282 	hack	egcs-pc532-ip6_mroute
    283 	cdate	09 Jul 2002
    284 	who	simonb
    285 	file	sys/arch/pc532/conf/Makefile.pc532 : 1.70
    286 	file	sys/arch/pc532/conf/files.pc532 : 1.47
    287 	descr
    288 		egcs 1.1.2 gets an "internal error--insn does not satisfy its
    289 		constraints" error compiling ip6_mroute.c with -O2 or greater.
    290 		-O1 works around this problem.
    291 	kcah
    292 
    293 	hack	gcc-pc532-duffs_device
    294 	cdate	Mon Oct 27 07:23:05 UTC 2003
    295 	who	simonb
    296 	file	sys/arch/pc532/conf/Makefile.pc532 : 1.71
    297 	file	sys/arch/pc532/conf/files.pc532 : 1.52
    298 	pr	GCC PR optimization/5230
    299 	descr
    300 		gcc incorrectly gives an "unreachable code at beginning of
    301 		switch statement" for a Duff's device construct in
    302 		arch/pc532/dev/ncr.c.  There is no way to disable just this
    303 		warning, so -Wno-error is turned on for this file.
    304 	kcah
    305 
    306 	hack	gcc332-cppmacro-ice
    307 	cdate	Sun Dec  7 12:48:33 UTC 2003
    308 	who	simonb
    309 	file	gnu/usr.bin/gcc3/libcpp/Makefile : 1.2
    310 	descr
    311 		gcc 3.3.2 gets an ICE when compiling cppmacro.c with -O2.
    312 		The hack is to use -O1 for this file.  Fixed in gcc
    313 		-current mainline, unable to work out where the fix is
    314 		right now.
    315 	kcah
    316 
    317 
    318 port	sh3
    319 
    320 	hack	gcc-sh3-sed
    321 	mdate	23 Apr 2002
    322 	who	thorpej
    323 	file	usr.bin/sed/Makefile	: 1.9 : 9 : 13
    324 	descr
    325 		The in-tree GCC 2.95.3-based compiler ICEs when building
    326 		with optimization for SuperH.  Hack is to build with -O0.
    327 	kcah
    328 
    329 
    330 port	sh5
    331 
    332 	hack	SuperH SH5 Toolchain Bugs
    333 	cdate	11 Jul 2002
    334 	who	scw
    335 	file	usr.sbin/ndbootd/ndbootd.c : 1.6
    336 	file	usr.sbin/traceroute/traceroute.c : 1.48
    337 	descr
    338 		The SuperH SH5 toolchain (2.97-sh5-010522) gets an internal
    339 		compiler error when assigning a bit-wise inverted value
    340 		under some circumstances.
    341 		Work around it by splitting the statement into two.
    342 	kcah
    343 
    344 	hack	SuperH SH5 Toolchain Bugs
    345 	cdate	17 May 2003
    346 	who	scw
    347 	file	lib/libpthread/pthread_lock.c : 1.7
    348 	descr
    349 		The SuperH SH5 toolchain generates incorrect PIC code when
    350 		faced with a symbol which is declared extern, but has local
    351 		scope due to being defined within an asm() statement (without
    352 		being declared .globl in that statement). Work around it by
    353 		adding the .globl.
    354 	kcah
    355 
    356 	hack	gcc 3.3.2 on sh5 - ICE compiling reload1.c at -O2
    357 	cdate	Sun Dec  7 19:44:05 GMT 2003
    358 	who	scw
    359 	file	gnu/usr.bin/gcc3/backend/Makefile : 1.13
    360 	descr
    361 		Gcc3 for sh5 gets an ICE compiling reload1.c at -O2.
    362 		Drop to -O1 for now when building for sh5.
    363 	kcah
    364 
    365 	hack	gcc 3.3.2 on sh5 - ICE compiling elf32.c/elf64.c at -O2
    366 	cdate	Sun Dec  7 21:10:46 GMT 2003
    367 	who	scw
    368 	file	gnu/lib/libbfd/Makefile : 1.39
    369 	descr
    370 		Gcc3 for sh5 gets an ICE compiling libbfd's elf32.c
    371 		and elf64.c at -O2.
    372 		Drop to -O1 for now when building for sh5.
    373 	kcah
    374 
    375 
    376 	hack	gcc 3.3.2 on sh5 - fatal warning compiling function.c
    377 	cdate	Sun Dec  7 19:44:05 GMT 2003
    378 	who	scw
    379 	file	gnu/usr.bin/gcc3/backend/Makefile : 1.13
    380 	descr
    381 		Gcc3 for sh5 issues a warning:
    382 		.../gnu/dist/gcc/gcc/function.c:4742: warning: `and' of
    383 		    mutually exclusive equal-tests is always 0.
    384 		This causes the build to fail because of -Werror.
    385 		Work-around by defining NOGCCERROR when building for sh5.
    386 	kcah
    387 
    388 	hack	gcc 3.3.3 on sh5 - ICE compiling rbtdb.c and rbtdb64.c
    389 	cdate	Thu Nov 11 00:35:33 UTC 2004
    390 	who	he
    391 	file	usr.sbin/bind/libdns/Makefile/1.2
    392 	descr
    393 		Gcc3 for sh5 gets an ICE compiling these files at -O2.
    394 		Drop to -O1 for now when building for sh5.
    395 	kcah
    396 
    397 	hack	gcc 3.3.3 nb3 on sh5 - ICE compiling bsd-comp.c
    398 	cdate	Thu May 25 23:05:20 UTC 2005
    399 	who	he
    400 	file	sys/lkm/net/bsdcomp/Makefile : 1.3
    401 	descr
    402 		Gcc3 for sh5 gets an ICE compiling this at -O2,
    403 		"could not split insn".  Drop to -O1 for sh5.
    404 	kcah
    405 
    406 port	sun2
    407 
    408 	hack	gcc 3.3.2/mdsetimage
    409 	cdate	Tue Oct 28 18:43:05 EST 2003
    410 	who	fredette
    411 	file	gnu/usr.sbin/mdsetimage/Makefile : 1.15
    412 	descr
    413 		mdsetimage.c causes cc1 to barf for as-yet unknown reasons.
    414 		this hack uses -O0 to avoid the problem.
    415 	kcah
    416 
    417 	hack	gcc 3.3.2/installboot/ffs.c
    418 	cdate	Tue Oct 28 18:43:05 EST 2003
    419 	who	fredette
    420 	file	usr.sbin/installboot/Makefile : 1.26
    421 	descr
    422 		ffs.c causes cc1 to barf for as-yet unknown reasons.  this
    423 		hack uses -O0 to avoid the problem.
    424 	kcah
    425 
    426 
    427 port	sun2 m68k
    428 
    429 	hack	gcc 3.3.2/gcc/ra-colorize.c
    430 	cdate	Wed Nov  5 11:03:13 EST 2003
    431 	who	mrg
    432 	file	gnu/usr.bin/gcc3/backend/Makefile : 1.11
    433 	descr
    434 		ra-colorize.c causes a whole spew of unreferenced .L* local
    435 		symbols.  using -O0 (or even -O2 reportedly) avoids the problem.
    436 	kcah
    437 
    438 port	sparc64
    439 
    440 	hack	disable optimzations for uvm_bio.c on 32 bit kernels
    441 	cdate	Sun Mar 21 14:14:04 MET 2004
    442 	who	martin
    443 	file	sys/arch/sparc64/conf/Makefile.sparc64 : 1.53-1.54
    444 	file	sys/arch/sparc64/conf/files.sparc64 : 1.93
    445 	descr
    446 		The sparc compiler miscompiles uvm_bio.c when using
    447 		any optimization. This results in ubc_release panics.
    448 	kcah
    449 
    450 port	macppc
    451 
    452 	hack	remove inline from rotate_{left,right}
    453 	cdate	Tue Feb 22 13:43:25 EST 2005
    454 	who	christos
    455 	file	src/dist/bind/lib/dns/rbt.c
    456 	descr
    457 		The macppc gcc-3.3 compiler miscompiles rbt.c when these
    458 		functions are inlined. The error is:
    459 		.* named[368]: rbt.c:1584: INSIST(child != (void *)0) >failed
    460 		.* named[368]: exiting (due to assertion failure)
    461 		This is reportedly fixed in gcc-3.4
    462 	kcah
    463 
    464 port	hppa
    465 
    466 	hack	hppa-gcc-3.3.3/grep/dfa.c
    467 	cdate	Sun Aug  8 08:34:32 PDT 2004
    468 	who	chs
    469 	file	gnu/usr.bin/grep/grep/Makefile : 1.4
    470 	descr
    471 		gcc 3.3.3 generates bad code for dfa.c with -O2,
    472 		reduce optimization to -O1 to avoid the bug.
    473 	kcah
    474 
    475 	hack	hppa boot-from-disk memory corruption
    476 	cdate	Wed May 18 06:56:07 PDT 2005
    477 	who	chs
    478 	file	src/sys/dev/scsipi/scsipiconf.h : 1.98
    479 	descr
    480 		There is some bug with DMA on hppa that corrupts scsipi_xfer
    481 		structures, but it only shows up when booting from disk.
    482 		For now, we'll add some padding to scsipi_xfer so that
    483 		the corrupted memory is not otherwise used.
    484 	kcah
    485 
    486 port	mips
    487 
    488 	hack	mips-shared-linker-load-address
    489 	cdate	Fri Oct  7 08:33:10 UTC 2005
    490 	who	simonb
    491 	file	src/sys/kern/exec_elf32.c : 1.107
    492 	descr
    493 		With COMPAT_16 or previous enabled (which enables
    494 		ELF_INTERP_NON_RELOCATABLE) a recent ld.elf_so will
    495 		load and run at address 0.  The check to fix this in
    496 		rev 1.107 only checks the first psection of the ELF
    497 		executable, which may not be loadable.  A more correct
    498 		fix is to check the first loadable psection instead of
    499 		just the first psection.
    500 	kcah
    501