HACKS revision 1.7
1 # $NetBSD: HACKS,v 1.7 2003/09/09 13:40:59 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 gcc 2.95/vax cannot handle __builtin_ffs() 31 cdate Fri Aug 23 21:31:15 CEST 2002 32 who ragge 33 port vax 34 file sys/lib/libkern/libkern.h : 1.42 35 descr 36 __builtin_ffs() is ifdef'd away if __vax__. Matt Thomas has added 37 this feature to GCC 3 so it can be removed when switching. 38 kcah 39 40 hack gcc 2.95.3 -O2 bug 41 cdate Sun Jan 6 23:17:28 UTC 2002 42 who lukem 43 port alpha 44 file sbin/newfs/mkfs.c : (all?) 45 pr 15156 46 descr 47 newfs built with gcc -O2 dumps core part-way through. 48 using -O1 avoids the problem 49 kcah 50 51 hack binutil-2.11-sparc64-pltrela 52 mdate 14 Aug 2001 53 who eeh 54 port sparc64 55 file libexec/ld.elf_so/reloc.c: 1.41 : 597 : 619 56 descr 57 The first for PLT entries are reserved. There is some disagreement 58 whether they should have associated relocation entries. Both the 59 SPARC 32-bit and 64-bit ELF specifications say that they should have 60 relocation entries, but the 32-bit SPARC binutils do not generate 61 them, and now the 64-bit SPARC binutils have stopped generating them 62 too. 63 64 To provide binary compatibility, we will check the first entry, if it 65 is reserved it should not be of the type JMP_SLOT. If it is JMP_SLOT, 66 then the 4 reserved entries were not generated and our index is 4 67 entries too far, so we frob the rela pointer. 68 kcah 69 70 hack gcc-arm32-schedule 71 mdate 04 May 2000 72 who is 73 file lib/libc/stdlib/strtoull.c : 1.3 : 78 : 81 74 file lib/libc/stdlib/strtouq.c : 1.15 : 73 : 76 75 pr 9613 76 descr 77 strtoull() was returning a wrong result for small numbers with bit 31 78 set. This is a gcc/arm32 compiler bug in gcc < 2.95.2. Adding 79 (void)&acc; works around it. 80 kcah 81 82 hack gcc-sparc64-memorysize 83 mdate 17 Sep 2000 84 who mrg 85 port sparc64 86 file lib/libc/hash/sha1.c : 1.6 : 78 : 129 : 162 : 189 87 file sys/lib/libkern/sha1.c : 1.6 : 78 : 129 : 162 : 189 88 file usr.sbin/bind/lib/Makefile : 1.14 : 87 : 91 89 descr 90 the normal SHA1Transform() function causes the sparc64 compiler to 91 use excessive amounts of memory attempting to optimise this function. 92 using no optimisation allows the function to build. this hack 93 splits the mathematical functions inside SHA1Transform() into 4 94 separate functions, which avoids the optimiser explosion. 95 kcah 96 97 hack gcc-sparc64-double-arguments 98 mdate 18 Sep 2000 99 who mrg 100 port sparc64 101 file xsrc/xc/lib/fonts/Type1/type1.c : 1.2 : 1461 : 1507 : 1702 : 1709 102 descr 103 in passing 17 "double" arguments to a function, gcc incorrectly tries 104 to use a register that doesn't exist, causing an internal error. this 105 hack changes the way arguments are passed to the function, such that 106 a pointer to a "double" (really an array) is passed, and the old 107 arguments are assigned within the function. 108 kcah 109 110 hack gcc-sparc64-gawk 111 mdate 28 Oct 2000 112 who mrg 113 port sparc64 114 file gnu/usr.bin/gawk/Makefile : 1.11 : 21 : 24 115 descr 116 gcc fails to build gawk properly, due to double floating point bugs. 117 this simple test program will fail to print ``ab'': 118 BEGIN { f = "abc"; print substr(f, 1, 2); exit } 119 the work around is simple: use -msoft-quad-float. 120 kcah 121 122 hack gcc-sparc64-libgcc 123 mdate 01 Dec 2001 124 who jmc 125 port sparc64 126 file gnu/lib/libgcc/Makefile : 1.29 : 24 : 27 127 descr 128 gcc fails to do double -> int conversions correctly without 129 soft-quad-float. Add it in there for the internal conversion 130 routines. This appears to be more than likely emulations bugs than 131 compiler bugs as the assembly looks correct on the surface. 132 133 kcah 134 135 hack gcc-sparc64-iostat-systat 136 mdate 04 Feb 2001 137 who mrg 138 port sparc64 139 file usr.sbin/iostat/Makefile : 1.17 : 7 : 10 140 file usr.bin/systat/Makefile : 1.23 : 6 : 9 141 descr 142 gcc fails to build iostat properly, due to double floating point bugs. 143 results will include "Inf" and other garbage. 144 the work around is simple: use -msoft-quad-float. 145 kcah 146 147 hack gcc-sparc64-nawk 148 mdate 25 Oct 2001 149 who martin 150 port sparc64 151 file usr.bin/awk/Makefile : 1.3 : 13 : 15 152 descr 153 Don't use long double on sparc64. 154 kcah 155 156 hack gcc-sparc64-ntp 157 mdate 12 Nov 2000 158 who martin 159 port sparc64 160 file usr.sbin/ntp/Makefile.inc : 1.5 : 17 : 19 161 descr 162 gcc fails to build ntpd properly, due to double floating point bugs. 163 Ntpd will fail to decode incoming packets; ntpdc -s will report 164 a delay, offset and dispersion of 0.0000 for all peers. 165 the work around is simple: use -msoft-quad-float. 166 kcah 167 168 hack gcc-sparc64-x_dhclient 169 mdate 27 Dec 2000 170 who mrg 171 port sparc64 172 file distrib/utils/x_dhclient/Makefile : 1.6 : 28 : 30 173 descr 174 gcc fails with an ICE while building dhclient's parse.c with -O2 175 and -Os. the work around is simple: don't use -Os. 176 kcah 177 178 hack lint-no-long-double 179 mdate 17 Aug 2001 180 who eeh 181 port sparc64 182 file usr.bin/xlint/lint1/param.h: 1.14 : 183 descr 184 Don't use long double on sparc64. 185 kcah 186 187 hack netstat ieee1394 address printing. 188 mdate 14 Nov 2000 189 who matt 190 file lib/libc/net/getnameinfo.c : 1.32 : 497 : 503 191 descr 192 Because the current implementation of IP over IEEE1394, the 193 fw device address contains more than just the IEEE1394 EUI-64. 194 So when printing out IEEE1394 addresses, ignore the extra stuff. 195 kcah 196 197 hack xterm vs. libterm 198 mdate 01 Aug 2000 199 who jdc 200 file xsrc/xc/programs/xterm/main.c : 1.2 : 3609 : 3614 201 pr 10383 202 descr 203 In order to extend the termcap string over 1023 bytes, a ZZ entry was 204 introduced to point to a memory location containing the full entry. 205 Without this hack, xterm will export a termcap containing the ZZ 206 entry, which will then be ignored by libterm. As xterm modifies the 207 exported termcap, this would cause those modifications to be ignored. 208 kcah 209 210 hack gcc-sh3-sed 211 mdate 23 Apr 2002 212 who thorpej 213 file usr.bin/sed/Makefile : 1.9 : 9 : 13 214 descr 215 The in-tree GCC 2.95.3-based compiler ICEs when building 216 with optimization for SuperH. Hack is to biuld with -O0. 217 kcah 218 219 hack gcc-unsigned-compare 220 cdate 09 Mar 2002 221 mdate 18 Mar 2002 222 who bjh21 223 port arm 224 file dist/bind/lib/nameser/ns_parse.c : 1.3 225 file dist/dhcp/minires/ns_parse.c : 1.3 226 file dist/dhcp/omapip/result.c : 1.2 227 file dist/dhcp/server/failover.c : 1.3 228 file gnu/dist/gawk/eval.c : 1.4 229 file gnu/dist/toolchain/bfd/bfd.c : 1.2 230 file gnu/dist/toolchain/bfd/format.c : 1.2 231 file gnu/dist/toolchain/gdb/target.c : 1.2 232 file sys/kern/vfs_subr.c : 1.172 233 descr When checking that a potentially-unsigned enum is >= 0, assign it 234 to an int first. This is necessary to avoid "comparison is always 235 true" warnings with -fshort-enums. Casting to an int really should 236 be enough, but turns out not to be. 237 kcah 238 239 hack wi-at-big-endian-bus 240 cdate 15 Mar 2002 241 who martin 242 file dev/ic/wireg.h 243 descr Add an option to access the underlying bus in big endian byte order 244 to work around deficiencies in bus_space_{read,write}_* macros. 245 Those don't allow the implementation of a proper pcmcia bus space 246 tag. 247 kcah 248 249 hack gcc 2.95.3 -O2 (-fgcse) bug 250 cdate Sun May 5 18:36:04 UTC 2002 251 who tsutsui 252 port macppc 253 file sys/arch/macppc/dev/adb_direct.c: 1.24 : 1895 : 1896 254 pr 16678 255 descr 256 gcc-2.95.3 does generates wrong code on optimization 257 by gcc -O2 (-fgcse), and adb_read_date_time() returns 258 wrong value on cuda system. 259 A null asm statement has been added to avoid this for workaround. 260 kcah 261 262 hack gcc-vax-libbz2 263 mdate 27 Jun 2002 264 who thorpej 265 port vax 266 file lib/libbz2/Makefile 267 descr 268 libbz2 is mis-compiled with optimization with GCC 2.95.3 269 on VAX. -O0 works around this problem. 270 kcah 271 272 hack egcs-pc532-ip6_mroute 273 cdate 09 Jul 2002 274 who simonb 275 port pc532 276 file sys/arch/pc532/conf/Makefile.pc532 : 1.70 277 file sys/arch/pc532/conf/files.pc532 : 1.47 278 descr 279 egcs 1.1.2 gets an "internal error--insn does not satisfy its 280 constraints" error compiling ip6_mroute.c with -O2 or greater. 281 -O1 works around this problem. 282 kcah 283 284 hack SuperH SH5 Toolchain Bugs 285 cdate 11 Jul 2002 286 who scw 287 port sh5 288 file usr.sbin/ndbootd/ndbootd.c : 1.6 289 file usr.sbin/traceroute/traceroute.c : 1.48 290 descr 291 The SuperH SH5 toolchain (2.97-sh5-010522) gets an internal 292 compiler error when assigning a bit-wise inverted value 293 under some circumstances. 294 Work around it by splitting the statement into two. 295 kcah 296 297 hack vax Toolchain bug 298 cdate 28 Mar 2003 299 who he 300 port vax 301 file sys/arch/vax/vax/intvec.S : 1.5 302 descr 303 Workaround for PR toolchain/20924. The assembler apparently 304 tries to range-check byte offsets when it doesn't have 305 sufficient information to make that decision. 306 Workaround uses `brw' instead of `brb' instruction. 307 kcah 308 309 hack specific knowledge of colours in curses code 310 cdate Sun Apr 6 11:05:24 BST 2003 311 who jdc 312 port all 313 file lib/libcurses/color.c : r1.24 314 descr 315 Swap red/blue and yellow/cyan colours for COLOR_OTHER. 316 Fix is to enhance libtermcap to understand terminfo-style % sequences. 317 See also: 318 http://mail-index.NetBSD.org/tech-userlevel/2003/04/06/0000.html 319 kcah 320 321 hack SuperH SH5 Toolchain Bugs 322 cdate 17 May 2003 323 who scw 324 port sh5 325 file lib/libpthread/pthread_lock.c : 1.7 326 descr 327 The SuperH SH5 toolchain generates incorrect PIC code when faced 328 with a symbol which is declared extern, but has local scope due 329 to being defined within an asm() statement (without being declared 330 .globl in that statement). Work around it by adding the .globl. 331 kcah 332 333 hack Compensation for differing types of LINUX_USRSTACK and USRSTACK 334 cdate 21 Aug 2003 335 who he 336 file sys/miscfs/procfs/procfs_linux.c : 1.14 337 descr 338 Not all ports have LINUX_USRSTACK and/or USRSTACK defined as 339 literals/constants, but refer to variables of a type which is 340 not "unsigned long", causing compilation of procfs_linux.c to 341 fail with "makes integer from pointer without a cast". This 342 is observed on e.g. the sun3 port. Ideally the "types" for 343 symbols should be consistent across all ports. 344 kcah 345
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