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HACKS revision 1.23
      1 # $NetBSD: HACKS,v 1.23 2003/11/06 00:37:14 he 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 
     88 port	vax
     89 
     90 	hack	gcc 2.95/vax cannot handle __builtin_ffs()
     91 	cdate	Fri Aug 23 21:31:15 CEST 2002
     92 	who	ragge
     93 	file	sys/lib/libkern/libkern.h : 1.42
     94 	descr
     95 		__builtin_ffs() is ifdef'd away if __vax__. Matt Thomas has
     96 		added this feature to GCC 3 so it can be removed when switching.
     97 	kcah
     98 
     99 	hack	gcc-vax-libbz2
    100 	mdate	27 Jun 2002
    101 	who	thorpej
    102 	file	lib/libbz2/Makefile
    103 	descr
    104 		libbz2 is mis-compiled with optimization with GCC 2.95.3
    105 		on VAX.  -O0 works around this problem.
    106 	kcah
    107 
    108 	hack	vax Toolchain bug
    109 	cdate	28 Mar 2003
    110 	who	he
    111 	file	sys/arch/vax/vax/intvec.S : 1.5
    112 	descr
    113 		Workaround for PR toolchain/20924.  The assembler apparently
    114 		tries to range-check byte offsets when it doesn't have
    115 		sufficient information to make that decision.
    116 		Workaround uses `brw' instead of `brb' instruction.
    117 	kcah
    118 
    119 	hack	vax gcc 2.95.3 -Wuninitialized workarounds
    120 	cdate	6 Nov 2003
    121 	who	he
    122 	file	sys/dev/bi/if_ni.c : 1.22
    123 	file	sys/arch/vax/vax/ctu.c : 1.20
    124 	descr
    125 		Workaround for gcc 2.95.3 failing to detect that certain
    126 		variables will be initialized; so that this code compiles
    127 		with -Wuninitialized.  Should be reviewed and possibly
    128 		reverted when gcc 3.3.2 is ready for vax.
    129 	kcah
    130 
    131 
    132 port	sparc64
    133 
    134 	hack	binutil-2.11-sparc64-pltrela
    135 	mdate	14 Aug 2001
    136 	who	eeh
    137 	file	libexec/ld.elf_so/arch/sparc64/mdreloc.c
    138 	descr
    139 		The first for PLT entries are reserved.  There is some
    140 		disagreement whether they should have associated relocation
    141 		entries.  Both the SPARC 32-bit and 64-bit ELF specifications
    142 		say that they should have relocation entries, but the 32-bit
    143 		SPARC binutils do not generate them, and now the 64-bit SPARC
    144 		binutils have stopped generating them too.
    145 
    146 		To provide binary compatibility, we will check the first entry,
    147 		if it is reserved it should not be of the type JMP_SLOT.  If it
    148 		is JMP_SLOT, then the 4 reserved entries were not generated and
    149 		our index is 4 entries too far, so we frob the rela pointer.
    150 	kcah
    151 
    152 
    153 port	arm
    154 
    155 	hack	gcc-unsigned-compare
    156 	cdate	09 Mar 2002
    157 	mdate	18 Mar 2002
    158 	who	bjh21
    159 	file	dist/bind/lib/nameser/ns_parse.c : 1.3
    160 	file	dist/dhcp/minires/ns_parse.c : 1.3
    161 	file	dist/dhcp/omapip/result.c : 1.2
    162 	file	dist/dhcp/server/failover.c : 1.3
    163 	file	gnu/dist/gawk/eval.c : 1.4
    164 	file	gnu/dist/toolchain/bfd/bfd.c : 1.2
    165 	file	gnu/dist/toolchain/bfd/format.c : 1.2
    166 	file	gnu/dist/toolchain/gdb/target.c : 1.2
    167 	file	sys/kern/vfs_subr.c : 1.172
    168 	descr	When checking that a potentially-unsigned enum is >= 0, assign
    169 		it to an int first.  This is necessary to avoid "comparison is
    170 		always true" warnings with -fshort-enums.  Casting to an int
    171 		really should be enough, but turns out not to be.
    172 	kcah
    173 
    174 	hack	gcc 3.3.x bug
    175 	cdate	Sun Oct 26 01:50:16 UTC 2003
    176 	who	lukem
    177 	file	usr.bin/newsyslog/newsyslog.c
    178 	pr	22986 23002 23217
    179 	descr
    180 		newsyslog fails with
    181 			newsyslog: config line 7: bad flags
    182 		solved when compiled with -fno-gcse-lm
    183 	kcah
    184 
    185 	hack	gcc 3.3.2/arm sys/kern/uipc_socket.c
    186 	cdate	Tue Oct 28 18:02:16 GMT 2003
    187 	who	skrll
    188 	file	sys/conf/arm/Makefile.arm : 1.19
    189 	descr
    190 		Performing a build.sh tools on a CATS with NFS mounted 
    191 		obj and src directories results in "panic: receive 1"
    192 		The hack is to compile sys/kern/uipc_socket.c with
    193 		-fno-strict-aliasing
    194 	kcah
    195 
    196 
    197 port	pc532
    198 
    199 	hack	egcs-pc532-ip6_mroute
    200 	cdate	09 Jul 2002
    201 	who	simonb
    202 	file	sys/arch/pc532/conf/Makefile.pc532 : 1.70
    203 	file	sys/arch/pc532/conf/files.pc532 : 1.47
    204 	descr
    205 		egcs 1.1.2 gets an "internal error--insn does not satisfy its
    206 		constraints" error compiling ip6_mroute.c with -O2 or greater.
    207 		-O1 works around this problem.
    208 	kcah
    209 
    210 	hack	gcc-pc532-duffs_device
    211 	cdate	Mon Oct 27 07:23:05 UTC 2003
    212 	who	simonb
    213 	file	sys/arch/pc532/conf/Makefile.pc532 : 1.71
    214 	file	sys/arch/pc532/conf/files.pc532 : 1.52
    215 	pr	GCC PR optimization/5230
    216 	descr
    217 		gcc incorrectly gives an "unreachable code at beginning of
    218 		switch statement" for a Duff's device construct in
    219 		arch/pc532/dev/ncr.c.  There is no way to disable just this
    220 		warning, so -Wno-error is turned on for this file.
    221 	kcah
    222 
    223 
    224 port	sh3
    225 
    226 	hack	gcc-sh3-sed
    227 	mdate	23 Apr 2002
    228 	who	thorpej
    229 	file	usr.bin/sed/Makefile	: 1.9 : 9 : 13
    230 	descr
    231 		The in-tree GCC 2.95.3-based compiler ICEs when building
    232 		with optimization for SuperH.  Hack is to biuld with -O0.
    233 	kcah
    234 
    235 
    236 port	sh5
    237 
    238 	hack	SuperH SH5 Toolchain Bugs
    239 	cdate	11 Jul 2002
    240 	who	scw
    241 	file	usr.sbin/ndbootd/ndbootd.c : 1.6
    242 	file	usr.sbin/traceroute/traceroute.c : 1.48
    243 	descr
    244 		The SuperH SH5 toolchain (2.97-sh5-010522) gets an internal
    245 		compiler error when assigning a bit-wise inverted value
    246 		under some circumstances.
    247 		Work around it by splitting the statement into two.
    248 	kcah
    249 
    250 	hack	SuperH SH5 Toolchain Bugs
    251 	cdate	17 May 2003
    252 	who	scw
    253 	file	lib/libpthread/pthread_lock.c : 1.7
    254 	descr
    255 		The SuperH SH5 toolchain generates incorrect PIC code when
    256 		faced with a symbol which is declared extern, but has local
    257 		scope due to being defined within an asm() statement (without
    258 		being declared .globl in that statement). Work around it by
    259 		adding the .globl.
    260 	kcah
    261 
    262 
    263 port	sun2
    264 
    265 	hack	gcc 3.3.2/mdsetimage
    266 	cdate	Tue Oct 28 18:43:05 EST 2003
    267 	who	fredette
    268 	file	gnu/usr.sbin/mdsetimage/Makefile : 1.15
    269 	descr
    270 		mdsetimage.c causes cc1 to barf for as-yet unknown reasons.
    271 		this hack ues -O0 to avoid the problem.
    272 	kcah
    273 
    274 	hack	gcc 3.3.2/installboot/ffs.c
    275 	cdate	Tue Oct 28 18:43:05 EST 2003
    276 	who	fredette
    277 	file	usr.sbin/installboot/Makefile : 1.26
    278 	descr
    279 		ffs.c causes cc1 to barf for as-yet unknown reasons.  this
    280 		hack ues -O0 to avoid the problem.
    281 	kcah
    282 
    283 
    284 port	sun2, m68k
    285 
    286 	hack	gcc 3.3.2/gcc/ra-colorize.c
    287 	cdate	Wed Nov  5 11:03:13 EST 2003
    288 	who	mrg
    289 	file	gnu/usr.bin/gcc/backend/Makefile : 1.11
    290 	descr
    291 		ra-colorize.c causes a whole spew of unreferenced .L* local
    292 		symbols.  using -O0 (or even -O2 reportedly) avoids the problem.
    293 	kcah
    294