NetBSD/doc/HACKS

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# $NetBSD: HACKS,v 1.46 2005/05/11 13:10:21 chs Exp $
#
# This file is intended to document workarounds for currently unsolved
# (mostly) compiler bugs.
#
# Format:
# hack title
# cdate creation date
# mdate mod date
# who responsible developer
# port ...
# affected ports, space separated, if not "all"
# file affected file : revision : line from : line to
# affected files and revision and line numbers describing hack
# multiple lines if necessary.
# pr NNNN ...
# problem reports this hack works around, if known. Space
# separated.
# regress src/regress/directory/where/test/found
# regression test directories, if available.
# descr
# insert short informal description (multi-line). (Longer ones
# should be in the PR database. More formal descriptions might
# be in the regress tree. See above).
# kcah
# closing bracket.
#
# this is a comment.
hack netstat ieee1394 address printing.
mdate 14 Nov 2000
who matt
file lib/libc/net/getnameinfo.c : 1.32 : 497 : 503
descr
Because the current implementation of IP over IEEE1394, the
fw device address contains more than just the IEEE1394 EUI-64.
So when printing out IEEE1394 addresses, ignore the extra stuff.
kcah
hack xterm vs. libterm
mdate 01 Aug 2000
who jdc
file xsrc/xc/programs/xterm/main.c : 1.2 : 3609 : 3614
pr 10383
descr
In order to extend the termcap string over 1023 bytes, a ZZ entry was
introduced to point to a memory location containing the full entry.
Without this hack, xterm will export a termcap containing the ZZ
entry, which will then be ignored by libterm. As xterm modifies the
exported termcap, this would cause those modifications to be ignored.
kcah
hack wi-at-big-endian-bus
cdate 15 Mar 2002
who martin
file dev/ic/wireg.h
descr Add an option to access the underlying bus in big endian byte order
to work around deficiencies in bus_space_{read,write}_* macros.
Those don't allow the implementation of a proper pcmcia bus space
tag.
kcah
hack specific knowledge of colours in curses code
cdate Sun Apr 6 11:05:24 BST 2003
who jdc
file lib/libcurses/color.c : r1.24
descr
Swap red/blue and yellow/cyan colours for COLOR_OTHER.
Fix is to enhance libtermcap to understand terminfo-style % sequences.
See also:
http://mail-index.NetBSD.org/tech-userlevel/2003/04/06/0000.html
kcah
hack Compensation for differing types of LINUX_USRSTACK and USRSTACK
cdate 21 Aug 2003
who he
file sys/miscfs/procfs/procfs_linux.c : 1.14
descr
Not all ports have LINUX_USRSTACK and/or USRSTACK defined as
literals/constants, but refer to variables of a type which is
not "unsigned long", causing compilation of procfs_linux.c to
fail with "makes integer from pointer without a cast". This
is observed on e.g. the sun3 port. Ideally the "types" for
symbols should be consistent across all ports.
kcah
hack GCC2 isn't C99
cdate 5 December 2003
who mrg
file gnu/dist/binutils/ld/ldlex.c: r1.2
descr
ldlex.c is generated from ldlex.l and we get macro redefinition
errors from it if __STDC_VERSION__ is not C99 compliant. This
hack forces NetBSD 1.6 and later systems to also include <stdint.h>
to get the relevant definitions. This hack should be backed out
when all platforms have switched away from GCC2.
kcah
hack gcc-strict-aliasing
cdate 6 August 2004
who junyoung
pr 26516
file src/usr.sbin/racoon/racoon/Makefile : 1.21
descr
GCC issues a warning "dereferencing type-punned pointer will break
strict-aliasing rules" when compiling
crypto/dist/kame/racoon/crypto/openssl.c with -O[23s]. Note that this
is due to use of type casting in a non-standard way in the code and
not a compiler bug. Once a new release of KAME with a proper fix
applied is imported this should be backed out.
kcah
port vax
hack gcc 2.95/vax doesn't have stdbool.h and gettext needs it
cdate Mon May 9 12:16:22 CDT 2005
who jmc
file gnu/usr.bin/gettext/Makefile.inc.prog 1.5
gnu/usr.bin/gettext/libgrep/Makefile 1.3
gnu/usr.bin/gettext/libnlspr/Makefile 1.5
gnu/usr.bin/gettext/libnlsut/Makefile 1.3
descr
The latest gettext assumes a C99 environment or at least
configure checks to work around this. As we don't use configure
provide a stdbool.h for vax builds locally in directories from
the template provided by the gettext code.
hack gcc 2.95/vax can't handle __used__ in mcount.c
cdate Fri May 6 14:30:53 CDT 2005
who jmc
file src/lib/libc/gmon/mcount.c 1.17
descr
Recent changes to mark this as __used__ to prevent optimization
away on sparc64 don't work on 2.95 vax. Ifdef'd back in the
old __unused__ if on vax.
hack gcc 2.95/vax cannot handle __builtin_ffs()
cdate Fri Aug 23 21:31:15 CEST 2002
who ragge
file sys/lib/libkern/libkern.h : 1.42
descr
__builtin_ffs() is ifdef'd away if __vax__. Matt Thomas has
added this feature to GCC 3 so it can be removed when switching.
hack gcc-vax-libbz2
mdate 27 Jun 2002
who thorpej
file lib/libbz2/Makefile
descr
libbz2 is mis-compiled with optimization with GCC 2.95.3
on VAX. -O0 works around this problem.
kcah
hack gawk
mdate 8 Nov 2003
who ragge
file gnu/usr.bin/gawk/Makefile
descr
gawk is mis-compiled with optimization with GCC 2.95.3
on VAX. -O0 works around this problem.
kcah
hack vax Toolchain bug
cdate 28 Mar 2003
who he
file sys/arch/vax/vax/intvec.S : 1.5
descr
Workaround for PR toolchain/20924. The assembler apparently
tries to range-check byte offsets when it doesn't have
sufficient information to make that decision.
Workaround uses `brw' instead of `brb' instruction.
kcah
hack vax gcc 2.95.3 -Wuninitialized workarounds
cdate 6 Nov 2003
who he
file sys/dev/bi/if_ni.c : 1.22
file sys/arch/vax/vax/ctu.c : 1.20
descr
Workaround for gcc 2.95.3 failing to detect that certain
variables will be initialized; so that this code compiles
with -Wuninitialized. Should be reviewed and possibly
reverted when gcc 3.3.2 is ready for vax.
kcah
hack vax gcc 2.95.3 structure initialization
cdat 13 May 2004
who cl
file sys/miscfs/kernfs/kernfs_vnops.c : 1.104
descr
Workaround for gcc 2.95.3 failing to initialize structures
and/or unions inside structures using nested designators.
Should be reverted when gcc >=3.3.3 is ready for vax.
kcah
hack vax gcc 2.95.3 needs -I. to build nslexer.c
cdat 6 Jun 2004
who mhitch
file lib/libc/arch/vax/Makefile.inc : 1.6
descr
It appears necessary to add -I. to CPPFLAGS when building
nslesxer.c. This may be caused by gcc 2.95.3 being used.
Should be reverted when a newer gcc is ready for vax.
kcah
hack vax gcc 2.95.3 doesn't understand "-std=c99"
cdat 5 April 2005
who tron
file src/share/mk/bsd.sys.mk
descr
We cannot use "-std=c99" for compiler warning level 4 and above
because gcc 2.95.3 doesn't support that option.
kcah
port sparc64
hack binutil-2.11-sparc64-pltrela
mdate 14 Aug 2001
who eeh
file libexec/ld.elf_so/arch/sparc64/mdreloc.c
descr
The first four PLT entries are reserved. There is some
disagreement whether they should have associated relocation
entries. Both the SPARC 32-bit and 64-bit ELF specifications
say that they should have relocation entries, but the 32-bit
SPARC binutils do not generate them, and now the 64-bit SPARC
binutils have stopped generating them too.
To provide binary compatibility, we will check the first entry,
if it is reserved it should not be of the type JMP_SLOT. If it
is JMP_SLOT, then the 4 reserved entries were not generated and
our index is 4 entries too far, so we frob the rela pointer.
kcah
port arm
hack gcc-unsigned-compare
cdate 09 Mar 2002
mdate 18 Mar 2002
who bjh21
file dist/bind/lib/nameser/ns_parse.c : 1.3
file dist/dhcp/minires/ns_parse.c : 1.3
file dist/dhcp/omapip/result.c : 1.2
file dist/dhcp/server/failover.c : 1.3
file gnu/dist/gawk/eval.c : 1.4
file gnu/dist/toolchain/bfd/bfd.c : 1.2
file gnu/dist/toolchain/bfd/format.c : 1.2
file gnu/dist/toolchain/gdb/target.c : 1.2
file sys/kern/vfs_subr.c : 1.172
descr When checking that a potentially-unsigned enum is >= 0, assign
it to an int first. This is necessary to avoid "comparison is
always true" warnings with -fshort-enums. Casting to an int
really should be enough, but turns out not to be.
kcah
hack gcc 3.3.2/arm sys/kern/uipc_socket.c
cdate Tue Oct 28 18:02:16 GMT 2003
who skrll
pr 23044
file sys/arch/arm/conf/Makefile.arm : 1.19
descr
Performing a build.sh tools on a CATS with NFS mounted
obj and src directories results in "panic: receive 1"
The hack is to compile sys/kern/uipc_socket.c with
-fno-strict-aliasing
kcah
port pc532
hack egcs-pc532-ip6_mroute
cdate 09 Jul 2002
who simonb
file sys/arch/pc532/conf/Makefile.pc532 : 1.70
file sys/arch/pc532/conf/files.pc532 : 1.47
descr
egcs 1.1.2 gets an "internal error--insn does not satisfy its
constraints" error compiling ip6_mroute.c with -O2 or greater.
-O1 works around this problem.
kcah
hack gcc-pc532-duffs_device
cdate Mon Oct 27 07:23:05 UTC 2003
who simonb
file sys/arch/pc532/conf/Makefile.pc532 : 1.71
file sys/arch/pc532/conf/files.pc532 : 1.52
pr GCC PR optimization/5230
descr
gcc incorrectly gives an "unreachable code at beginning of
switch statement" for a Duff's device construct in
arch/pc532/dev/ncr.c. There is no way to disable just this
warning, so -Wno-error is turned on for this file.
kcah
hack gcc332-cppmacro-ice
cdate Sun Dec 7 12:48:33 UTC 2003
who simonb
file gnu/usr.bin/gcc3/libcpp/Makefile : 1.2
descr
gcc 3.3.2 gets an ICE when compiling cppmacro.c with -O2.
The hack is to use -O1 for this file. Fixed in gcc
-current mainline, unable to work out where the fix is
right now.
kcah
port sh3
hack gcc-sh3-sed
mdate 23 Apr 2002
who thorpej
file usr.bin/sed/Makefile : 1.9 : 9 : 13
descr
The in-tree GCC 2.95.3-based compiler ICEs when building
with optimization for SuperH. Hack is to build with -O0.
kcah
port sh5
hack SuperH SH5 Toolchain Bugs
cdate 11 Jul 2002
who scw
file usr.sbin/ndbootd/ndbootd.c : 1.6
file usr.sbin/traceroute/traceroute.c : 1.48
descr
The SuperH SH5 toolchain (2.97-sh5-010522) gets an internal
compiler error when assigning a bit-wise inverted value
under some circumstances.
Work around it by splitting the statement into two.
kcah
hack SuperH SH5 Toolchain Bugs
cdate 17 May 2003
who scw
file lib/libpthread/pthread_lock.c : 1.7
descr
The SuperH SH5 toolchain generates incorrect PIC code when
faced with a symbol which is declared extern, but has local
scope due to being defined within an asm() statement (without
being declared .globl in that statement). Work around it by
adding the .globl.
kcah
hack gcc 3.3.2 on sh5 - ICE compiling reload1.c at -O2
cdate Sun Dec 7 19:44:05 GMT 2003
who scw
file gnu/usr.bin/gcc3/backend/Makefile : 1.13
descr
Gcc3 for sh5 gets an ICE compiling reload1.c at -O2.
Drop to -O1 for now when building for sh5.
kcah
hack gcc 3.3.2 on sh5 - ICE compiling elf32.c/elf64.c at -O2
cdate Sun Dec 7 21:10:46 GMT 2003
who scw
file gnu/lib/libbfd/Makefile : 1.39
descr
Gcc3 for sh5 gets an ICE compiling libbfd's elf32.c
and elf64.c at -O2.
Drop to -O1 for now when building for sh5.
kcah
hack gcc 3.3.2 on sh5 - fatal warning compiling function.c
cdate Sun Dec 7 19:44:05 GMT 2003
who scw
file gnu/usr.bin/gcc3/backend/Makefile : 1.13
descr
Gcc3 for sh5 issues a warning:
.../gnu/dist/gcc/gcc/function.c:4742: warning: `and' of
mutually exclusive equal-tests is always 0.
This causes the build to fail because of -Werror.
Work-around by defining NOGCCERROR when building for sh5.
kcah
hack gcc 3.3.3 on sh5 - ICE compiling rbtdb.c and rbtdb64.c
cdate Thu Nov 11 00:35:33 UTC 2004
who he
file usr.sbin/bind/libdns/Makefile/1.2
descr
Gcc3 for sh5 gets an ICE compiling these files at -O2.
Drop to -O1 for now when building for sh5.
kcah
port sun2
hack gcc 3.3.2/mdsetimage
cdate Tue Oct 28 18:43:05 EST 2003
who fredette
file gnu/usr.sbin/mdsetimage/Makefile : 1.15
descr
mdsetimage.c causes cc1 to barf for as-yet unknown reasons.
this hack uses -O0 to avoid the problem.
kcah
hack gcc 3.3.2/installboot/ffs.c
cdate Tue Oct 28 18:43:05 EST 2003
who fredette
file usr.sbin/installboot/Makefile : 1.26
descr
ffs.c causes cc1 to barf for as-yet unknown reasons. this
hack uses -O0 to avoid the problem.
kcah
port sun2 m68k
hack gcc 3.3.2/gcc/ra-colorize.c
cdate Wed Nov 5 11:03:13 EST 2003
who mrg
file gnu/usr.bin/gcc3/backend/Makefile : 1.11
descr
ra-colorize.c causes a whole spew of unreferenced .L* local
symbols. using -O0 (or even -O2 reportedly) avoids the problem.
kcah
port sparc64
hack disable optimzations for uvm_bio.c on 32 bit kernels
cdate Sun Mar 21 14:14:04 MET 2004
who martin
file sys/arch/sparc64/conf/Makefile.sparc64 : 1.53-1.54
file sys/arch/sparc64/conf/files.sparc64 : 1.93
descr
The sparc compiler miscompiles uvm_bio.c when using
any optimization. This results in ubc_release panics.
kcah
port macppc
hack remove inline from rotate_{left,right}
cdate Tue Feb 22 13:43:25 EST 2005
who christos
file src/dist/bind/lib/dns/rbt.c
descr
The macppc gcc-3.3 compiler miscompiles rbt.c when these
functions are inlined. The error is:
.* named[368]: rbt.c:1584: INSIST(child != (void *)0) >failed
.* named[368]: exiting (due to assertion failure)
This is reportedly fixed in gcc-3.4
kcah
port hppa
hack hppa-gcc-3.3.3/grep/dfa.c
cdate Sun Aug 8 08:34:32 PDT 2004
who chs
file gnu/usr.bin/grep/grep/Makefile : 1.4
descr
gcc 3.3.3 generates bad code for dfa.c with -O2,
reduce optimization to -O1 to avoid the bug.
kcah