[BACK]Return to HACKS CVS log [TXT][DIR] Up to [cvs.NetBSD.org] / src / doc

File: [cvs.NetBSD.org] / src / doc / HACKS (download)

Revision, Sun Nov 3 11:41:57 2019 UTC (15 months, 3 weeks ago) by martin
Branch: netbsd-9
CVS Tags: netbsd-9-1-RELEASE, netbsd-9-0-RELEASE, netbsd-9-0-RC2, netbsd-9-0-RC1
Changes since 1.190: +10 -1 lines

Pull up following revision(s) (requested by rin in ticket #392):

	doc/HACKS: revision 1.195
	doc/HACKS: revision 1.196
	external/bsd/jemalloc/lib/Makefile.inc: revision 1.11
	external/bsd/jemalloc/include/jemalloc/internal/jemalloc_internal_defs.h: revision 1.11

PR/54307: Rin Okuyama: Lots of jemalloc assertions in latest -current

Workaround for random crash of userland binaries, as reported in
PR port-alpha/54307.

If rtree.c and tcache.c are compiled with -O0, userland just works
without problems as far as I can see. Alternately, you can specify
-DJEMALLOC_DEBUG to avoid random crash. Smells like compiler bug,
or wrong coding which relies on some undefined behavior.

Anyway, we need to pull this up into netbsd-9 asap.

Describe workaround for PR port-alpha/54307.

Describe that both GCC 7.4 and 8.3 fail in the last entry.

# $NetBSD: HACKS,v 2019/11/03 11:41:57 martin 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	static linking with libpthread
mdate	7 May 2019
who	maya
file	lib/libpthread/Makefile 1.92 -> 1.94
	To avoid some libc thread stub functions being picked up
	in static builds, link pthread as one section.

hack	gcc-5.3 optimizes memset+malloc -> calloc inside calloc
mdate	4 May 2016
who	christos
file	external/gpl2/lib/libmalloc/lib/Makefile 1.3 -> 1.5
	resulting in infinite recursion; we prevent this with

hack	turn off tree-vrp for parts of ufs_lookup.c
mdate	28 April 2016
who	mrg christos
file	src/sys/ufs/ufs/ufs_lookup.c : 1.144
pr	51094
	with -ftree-vrp enabled in ufs_lookup.c sometimes bad dir
	panicks are see.

hack	netstat ieee1394 address printing.
mdate	14 Nov 2000
who	matt
file	lib/libc/net/getnameinfo.c	: 1.32 : 497 : 503
	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.

hack	xterm vs. libterm
mdate	01 Aug 2000
who	jdc
file	xsrc/xc/programs/xterm/main.c	: 1.2 : 3609 : 3614
pr	10383
	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.

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

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
	Swap red/blue and yellow/cyan colours for COLOR_OTHER.
	Fix is to enhance libtermcap to understand terminfo-style % sequences.
	See also:

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
	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.

hack	gcc4 wrong uninitialized variable
mdate	10 May 2006
who	mrg
file	bin/ksh/eval.c			: 1.6
file	bin/sh/histedit.c		: 1.39
file	bin/sh/parser.c			: 1.60
file	crypto/dist/heimdal/kdc/524.c	: 1.10
file	crypto/dist/ssh/sftp.c		: 1.20
file	crypto/dist/ssh/ssh-keysign.c	: 1.11
file	dist/ipf/lib/hostname.c		: 1.2
file	dist/ipf/tools/ipmon.c		: 1.8
file	dist/ntp/ntpd/ntp_request.c	: 1.4
file	dist/ntp/ntpd/refclock_shm.c	: 1.4
file	dist/ntp/sntp/timing.c		: 1.3
file	dist/pppd/pppstats/pppstats.c	: 1.3
file	dist/smbfs/lib/smb/rap.c	: 1.6
file	dist/tcpdump/print-zephyr.c	: 1.5
file	distrib/utils/sysinst/aout2elf.c : 1.12
file	gnu/libexec/uucp/uucico/uucico.c : 1.6
file	lib/libc/citrus/citrus_csmapper.c : 1.6
file	lib/libc/citrus/citrus_pivot_factory.c : 1.5
file	lib/libc/inet/inet_cidr_ntop.c	: 1.3
file	lib/libc/inet/inet_ntop.c	: 1.3
file	lib/libc/stdio/vfwprintf.c	: 1.8
file	libexec/ld.elf_so/arch/m68k/mdreloc.c : 1.20
file	libexec/ld.elf_so/arch/powerpc/ppc_reloc.c : 1.40
file	libexec/ld.elf_so/arch/sh3/mdreloc.c : 1.22
file	libexec/ld.elf_so/arch/sparc/mdreloc.c : 1.39
file	libexec/ld.elf_so/arch/sparc64/mdreloc.c : 1.39
file	libexec/ld.elf_so/arch/vax/mdreloc.c	: 1.21
file	libexec/ld.elf_so/arch/x86_64/mdreloc.c	: 1.27
file	sbin/fsck_ext2fs/dir.c		: 1.19
file	sbin/routed/rtquery/rtquery.c	: 1.18
file	sys/arch/amd64/amd64/pmap.c	: 1.26
file	sys/arch/i386/pci/piixpcib.c	: 1.4
file	sys/arch/m68k/m68k/pmap_motorola.c	: 1.4
file	sys/crypto/cast128/cast128.c	: 1.9
file	sys/ddb/db_command.c		: 1.86
file	sys/dev/cardbus/cardbus_map.c	: 1.21
file	sys/dev/fss.c			: 1.25
file	sys/dev/ic/igsfb.c		: 1.39
file	sys/dev/ic/mb86950.c		: 1.5
file	sys/dev/ic/midway.c		: 1.71
file	sys/dev/kttcp.c			: 1.18
file	sys/dev/rasops/rasops_bitops.h	: 1.9
file	sys/dev/pci/cmpci.c		: 1.31
file	sys/dev/pci/machfb.c		: 1.45
file	sys/dev/usb/ohci.c		: 1.174
file	sys/dev/usb/uhci.c		: 1.196
file	sys/dev/rasops/rasops_bitops.h	: 1.9
file	sys/dist/ipf/netinet/ip_nat.c	: 1.10
file	sys/dist/ipf/netinet/ip_rpcb_pxy.c : 1.8
file	sys/dist/pf/net/pf.c		: 1.22
file	sys/fs/udf/udf_vnops.c		: 1.4
file	sys/kern/kern_sig.c		: 1.219
file	sys/kern/tty.c			: 1.181
file	sys/net/bpf.c			: 1.116
file	sys/net/zlib.c			: 1.26
file	sys/netccitt/if_x25subr.c	: 1.37
file	sys/netinet/in.c		: 1.107
file	sys/netsmb/smb_smb.c		: 1.27
file	sys/netsmb/smb_trantcp.c	: 1.22
file	sys/nfs/nfs_serv.c		: 1.108
file	sys/nfs/nfs_socket.c		: 1.129
file	sys/nfs/nfs_syscalls.c		: 1.91
file	sys/ufs/lfs/lfs_vfsops.c	: 1.207 [also (char *)]
file	usr.bin/ftp/ftp.c		: 1.140
file	usr.bin/find/function.c		: 1.54
file	usr.bin/mail/tty.c		: 1.20
file	usr.bin/msgc/msg_sys.def	: 1.33-1.34
file	usr.bin/nl/nl.c			: 1.7
file	usr.bin/systat/keyboard.c	: 1.23
file	usr.bin/usbhidctl/usbhid.c	: 1.29
file	usr.bin/vi/cl/cl_read.c		: 1.5
file	usr.bin/vi/ex/ex_cscope.c	: 1.12
file	usr.bin/vi/ex/ex_tag.c		: 1.19
file	usr.bin/vi/vi/v_txt.c		: 1.15
file	usr.sbin/altq/altqstat/qdisc_rio.c : 1.4
file	usr.sbin/cron/do_command.c	: 1.19
file	usr.sbin/timed/timed/slave.c	: 1.15
	GCC 4.1 gets many uninitialised variable warnings wrong.  We should
	really audit all the old hacks like this when older compilers are
	removed from the tree, as many are probably no longer required.
	The problem is that it does not recognize initialization via function
	call pointer. I.e.
		int p;
	does not mark p as initialized.

hack	gcc4 pointer sign and strict aliasing problems
mdate	10 May 2006
who	mrg
file	bin/ed/Makefile			: 1.33
file	distrib/utils/sysinst/Makefile.inc : 1.44
file	distrib/utils/x_dhclient/Makefile : 1.15
file	games/bcd/Makefile		: 1.5
file	games/dab/Makefile		: 1.5
file	games/larn/Makefile		: 1.17
file	games/pom/Makefile		: 1.5
file	lib/libasn1/Makefile		: 1.26
file	lib/libcrypt/Makefile		: 1.17
file	lib/libgssapi/Makefile		: 1.16
file	lib/libhdb/Makefile		: 1.20
file	lib/libkadm5clnt/Makefile	: 1.21
file	lib/libkadm5srv/Makefile	: 1.25
file	lib/libkrb5/Makefile		: 1.35
file	lib/libssh/Makefile		: 1.6
file	lib/libtelnet/Makefile		: 1.26
file	libexec/getty/Makefile		: 1.14
file	libexec/kadmind/Makefile	: 1.19
file	libexec/kpasswdd/Makefile	: 1.14
file	sbin/atactl/Makefile		: 1.3
file	sbin/cgdconfig/Makefile		: 1.7
file	sbin/clri/Makefile		: 1.13
file	sbin/dkctl/Makefile		: 1.4
file	sbin/dump/Makefile		: 1.33
file	sbin/fdisk/Makefile		: 1.35
file	sbin/fsck_ext2fs/Makefile	: 1.11
file	sbin/fsck_ffs/Makefile		: 1.29
file	sbin/fsdb/Makefile		: 1.18
file	sbin/mount_smbfs/Makefile	: 1.4
file	sbin/newfs/Makefile		: 1.30
file	sbin/newfs_sysvbfs/Makefile	: 1.2
file	sbin/restore/Makefile		: 1.23
file	sbin/veriexecctl/Makefile	: 1.11
file	sys/lib/libsa/Makefile		: 1.59
file	sys/arch/evbarm/adi_brh/brh_machdep.c : 1.24
file	usr.bin/awk/Makefile		: 1.9
file	usr.bin/crontab/Makefile	: 1.24
file	usr.bin/ctags/Makefile		: 1.8
file	usr.bin/gzip/Makefile		: 1.10
file	usr.bin/ssh/sftp/Makefile	: 1.10
file	usr.bin/ssh/ssh/Makefile	: 1.25
file	usr.bin/vi/build/Makefile	: 1.26
file	usr.bin/telnet/Makefile		: 1.40
file	usr.bin/tn3270/tn3270/Makefile	: 1.36
file	usr.bin/tr/Makefile		: 1.4
file	usr.sbin/amd/amd/Makefile	: 1.27
file	usr.sbin/amd/amq/Makefile	: 1.14
file	usr.sbin/amd/libamu/Makefile	: 1.20
file	usr.sbin/amd/pawd/Makefile	: 1.5
file	usr.sbin/bind/Makefile.inc	: 1.22
file	usr.sbin/bind/libdns/Makefile	: 1.3
file	usr.sbin/bind/named/Makefile	: 1.17
file	usr.sbin/bootp/bootptest/Makefile : 1.2
file	usr.sbin/chrtbl/Makefile	: 1.6
file	usr.sbin/cron/Makefile		: 1.12
file	usr.sbin/dhcp/Makefile.inc	: 1.20
file	usr.sbin/hprop/Makefile		: 1.13
file	usr.sbin/installboot/Makefile	: 1.35
file	usr.sbin/ipf/ipftest/Makefile	: 1.32
file	usr.sbin/isdn/isdnd/Makefile	: 1.6
file	usr.sbin/isdn/isdnmonitor/Makefile : 1.3
file	usr.sbin/isdn/isdntel/Makefile	: 1.2
file	usr.sbin/isdn/isdntrace/Makefile : 126
file	usr.sbin/mopd/common/Makefile	: 1.10
file	usr.sbin/mopd/mopd/Makefile	: 1.9
file	usr.sbin/mopd/mopprobe/Makefile	: 1.7
file	usr.sbin/makefs/Makefile	: 1.17
file	usr.sbin/mscdlabel/Makefile	: 1.5
file	usr.sbin/pkg_install/add/Makefile : 1.7
file	usr.sbin/pkg_install/create/Makefile : 1.5
file	usr.sbin/pkg_install/lib/Makefile : 1.28
file	usr.sbin/ntp/ntpd/Makefile	: 1.10/1.11
file	usr.sbin/ntp/ntptime/Makefile	: 1.4/1.5
file	usr.sbin/pppd/Makefile.inc	: 1.3
file	usr.sbin/pppd/pppd/Makefile	: 1.38
file	usr.sbin/rarpd/Makefile		: 1.10
file	usr.sbin/rbootd/Makefile	: 1.10
file	usr.sbin/rpc.pcnfsd/Makefile	: 1.17
file	usr.sbin/tcpdump/Makefile	: 1.42
	GCC 4.1 warns on pointer sign comparision/assignments and lots of
	code does not conform.  For now we use -Wno-pointer-sign and

hack	disable ctf for gcc-4.8 build
mdate	April 3 2014
who	christos
file	external/gpl3/gcc/usr.bin/Makefile.frontend	: 1.4
file	external/gpl3/gcc/usr.bin/Makefile.backend	: 1.5
	nbctfconvert -g -L VERSION -g fold-const.o
	ERROR: fold-const.c: failed to get mapping for tid 79154 \
		((null)) <13532>

hack	emacs aborting on exit (libgcc issue)
mdate	7 November 2011
who	christos
file	external/gpl3/gcc/dist/gcc/unwind-dw2-fde.c : 1.2
	GCC 4.5.3 now calls __unregister_frame_info_bases() on unloading/exit
	to do just that. If the symbol requested is not found, then it aborts.
	emacs 23.3 triggers this assertion. For now disable aborting, and
	silently ignore.

hack	cross-building hack on Darwin
mdate	20 July 2008
who	agc
file	src/distrib/common/Makefile.mdset	: 1.33
	Darwin has problems with getopt() when used in mdsetimage -v,
	due to the difference between BSD and libiberty() getopt
	implementations, more fully described in
	and the subsequent thread.  For just now, we just have an ugly
	workaround not to call mdsetimage with the -v argument on Darwin

hack	avoid rebuilding asn1 libraries
mdate	03 August 2008
who	veego
file	src/crypto/dist/heimdal/lib/asn1/gen.c	: 1.10
file	src/lib/libasn1/Makefile	: 1.32
file	src/lib/libhdb/Makefile	: 1.23
file	src/lib/libgssapi/Makefile	: 1.20
file	src/lib/libhx509/Makefile	: 1.3
pr	9702 39185
	asn1_compile does not check if generated header files do not have to
	be rebuild.
	Generate .hx files and copy it in the Makefiles if they changed.

hack	Disable fortification for /usr/bin/makeinfo
cdata	24 Mar 2014
who	tron
file	src/external/gpl2/texinfo/bin/makeinfo/Makefile	: 1.1
pr	N/A
	If "makeinfo" is compiled with "-D_FORTIFY_SOURCE=2" using GCC 4.8.3
	it fails to process certain texinfo files, e.g. "cl.texi"
	included in the Emacs 24.3 distribution.

hack	Disable Stack Smash Protection for /usr/X11R7/bin/xauth
cdata	05 Apr 2014
who	tron
file	src/external/mit/xorg/bin/xauth/Makefile	: 1.4
pr	N/A
	If "xauth" is compile with "USE_SSP" set to "yes" it fails
	mysteriously with an error message like this:

	/usr/X11R7/bin/xauth:  file /foo/bar/.Xauthority does not exist
	/usr/X11R7/bin/xauth:  unable to link authority file /foo/bar/.Xauthority, use /foo/bar/.Xauthority

	The compiler seems to get confused about the two filename variables
	used in the link(2) system call.

hack	g++ 5.x barfs on volatile in constexpr initializers
cdata	27 Aug 2015
who	pooka
file	src/lib/libpthread/pthread_types.h	: 1.17
pr	lib/49989
	Trying to use e.g. pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER
	in C++ results in:
		error: temporary of non-literal type '__pthread_mutex_st'
		in a constant expression
		constexpr mutex() _NOEXCEPT : __m_(PTHREAD_MUTEX_INITIALIZER) {}
		include/pthread_types.h:101:8: note: '__pthread_mutex_st' is
		not literal because:
		struct __pthread_mutex_st {
		include/pthread_types.h:103:17: note:   non-static data
		member '__pthread_mutex_st::ptm_errorcheck' has volatile type
		pthread_spin_t ptm_errorcheck;

hack	libm cabs{,f,l} and g++
cdata	11 Jan 2016
who	christos
pr	lib/50646
file	src/external/gpl3/gcc.old/dist/libstdc++-v3/include/std/complex : 1.2
file	src/external/gpl3/gcc/dist/libstdc++-v3/include/std/complex : 1.2
	Our cabs and cabsf have a different argument format on some architectures
	and for that we have created in libm/compat_cabs{,f}.c. The standard
	versions in libc are __c99_cabs{,f,l} and there are __RENAME()'s in
	<complex.h>. G++ uses __builtin_cabs{,f,l} to implement those and they
	translate by default to cabs{,f,l} which gets defined to cabs{,f} (the
	wrong function) and an undefined cabsl. I've changed <complex> to use
	the __c99_cabs{,f,l} directly. Using the __builtin_cabs{,f,l} in gcc is
	still broken.

port	vax

	hack	gcc4/vax ICE
	who	tsutsui
	file	sys/arch/vax/conf/Makefile.vax
		GCC4 on vax gets ICE on compiling sys/ddb/db_command.c.
		-fno-tree-ter prevents it so add it to COPTS.

	hack	gcc4/vax compiler crash
	cdate	Fri Jun 30 22:39:12 PDT 2006
	who	mrg
	file	bin/csh/Makefile	: 1.27
	file	lib/i18n_module/UTF7/Makefile	: 1.2
		GCC4 on vax crashes.  -O0 stops it happening so far...

	hack	declare boolean_t in two IPF user-mode programs
	cdate	Tue Mar  7 19:19:20 CET 2006
	who	he
	file	dist/ipf/ipsend/iptests.c : 1.8
		dist/ipf/ipsend/sock.c : 1.7
		The IPF user-mode programs ipsend and iptest first
		include <sys/types.h> without _KERNEL defined, and
		later include <sys/file.h> with _KERNEL defined.
		This causes a build failure when building for vax,
		since <sys/device.h> ends up being included without
		bollean_t being defined by <sys/types.h>.
		Build failure and further details documented in

	hack	pcc 0.9.9 large string literals
	cdat	8 July 2008
	who	gmcgarry
	file	sys/conf/param.c : 1.58
		Workaround for pcc 0.9.9 not handling large string literals
		which causes kernels with 'options INCLUDE_CONFIG_FILE' to
		fail compilation.
		There is a proposal on the pcc mailing list to stuff config
		file in ELF section.

	hack	xorg warnings
	cdat	30 July 2008, 3 June, 2013
	who	mrg
	file	external/mit/xorg/lib/libSM/Makefile : 1.2
		external/mit/xorg/lib/libX11/Makefile.libx11 : 1.10
		external/mit/xorg/lib/libXext/Makefile : 1.2
		external/mit/xorg/lib/libXfont/Makefile : 1.2
		Disable several warnings or use -Wno-error across Xorg sources
		while we get them working

	hack	32 bit time leftovers
	cdat	11 January 2009
	who	christos
	file	lib/libc/time/localtime.c : 1.41
		lib/libc/time/zic.c : 1.23
		The timezone compiled files still contain 32 bit time_t
		quantities. I did not want to version the files because
		the ``parser'' is too ugly for words. What needs to be
		done, is to rewrite the parser from scratch also to avoid
		potential core-dumps from parsing invalid files.

	hack	32 bit time leftovers
	cdat	11 January 2009
	who	christos
	file	various
		Many filesystem on-disk formats have 32 bit times.

	hack	gcc 4.5 fsdb miscompile
	date	Sat Nov  9 11:03:02 EST 2013
	who	christos
	file	src/sbin/fsdb/Makefile : 1.36 (and earlier)
		src/sbin/fsdb/fsdb.c: In function 'findblk':
		src/sbin/fsdb/fsdb.c:610:1: error: unrecognizable insn:
		(insn 941 940 942 134 src/sbin/fsdb/fsdb.c:589 (set (reg:SI 604)
		    (subreg:SI (mem/s/j:DI (plus:SI (mult:SI (reg:SI 602)
                        (const_int 8 [0x8]))
                    (reg/f:SI 601)) [0 curinode.99_378->dp2.di_ib S8 A32]) 4)) \
			-1 (nil))
		src/sbin/fsdb/fsdb.c:610:1: internal compiler error: in \
		extract_insn, at recog.c:2103

	hack	gcc 4.8 gcc miscompiles
	date	Sat Nov  9 16:35:18 EST 2013
	who	christos
	file	distrib/utils/x_ping/Makefile
	file	distrib/vax/miniroot/Makefile.inc
	file	distrib/vax/ramdisk/Makefile
	file	external/gpl3/gdb/lib/libdecnumber/Makefile
	file	sbin/fsdb/Makefile
	file	sbin/newfs_ext2fs/Makefile
	file	sbin/ping/Makefile
	file	usr.sbin/lmcconfig/Makefile
	file	usr.sbin/mtrace/Makefile
		internal compiler error: in change_address_1, at emit-rtl.c:2019
		internal compiler error: in change_address_1, at emit-rtl.c:2019
		internal compiler error: in change_address_1, at emit-rtl.c:2019
		internal compiler error: in change_address_1, at emit-rtl.c:2019
		internal compiler error: in reload_combine_note_use,
		at postreload.c:1561
		internal compiler error: in change_address_1, at emit-rtl.c:2019
		internal compiler error: in reload_combine_note_use,
		at postreload.c:1561
		internal compiler error: in change_address_1, at emit-rtl.c:2019

	hack	gcc 5.4 cc1 miscompile
	date	Tue Feb 14 07:19:57 JST 2017
	who	rin
	pr	port-vax/51967
	file	external/gpl3/gcc/usr.bin/backend/Makefile : 1.35
		cc1 aborts due to SIGILL when compiling the sample code attached
		to the PR. As a workaround, compile dse.c with -O0.

	hack	libssh miscompile
	cdate	Tue Feb 14 17:58:06 JST 2017
	mdate	Tue Feb 14 18:57:39 JST 2017
	who	rin
	file	crypto/external/bsd/openssh/lib/Makefile : 1.20
		poly1305.c and umac.c are miscompiled, which results in login
		failure to/from external hosts via ssh.

	hack	mandoc miscompile
	date	Tue Feb 14 18:03:05 JST 2017
	who	rin
	file	external/bsd/mdocml/lib/libmandoc/Makefile : 1.8
		mandoc(1) receives SIGILL in in_line_argn() from mdoc_macro.c.

	hack	libX11 miscompile
	date	Thu Feb 16 10:00:22 JST 2017
	who	rin
	file	src/external/mit/xorg/lib/libX11/Makefile.libx11 : 1.18
		lcWrap.c is miscompiled, which results in input failure via XIM.
		Besides, some clients, e.g., pkgsrc/x11/kterm, receive SIGSEGV.

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/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.

	hack	gcc-4.5 arm CNAME hostname lookup failure on
		certain DNS environment (probably -ftree-ter problem)
	cdate	Sat Dec 24 04:59:00 UTC 2011
	who	tsutsui
	file	lib/libc/net/Makefile.inc 1.79
	descr	Hostname lookup against CNAMEs by some commands fails
		on certain DNS environments if lib/libc/net/gethnamaddr.c
		(ping(8) etc) and lib/libc/net/getaddrinfo.c (ftp(1) etc)
		are compiled with -O2, even though nslookup(1) against
		the same CNAME returns proper hostname.
		They works properly if compiled with -O2 -fno-tree-ter.
		Also -O2 fails but -O2 -fno-tree-ter works on the following
		test case in gcc bugzilla:

	hack	gcc-4.5 arm without -fno-tree-vrp generate broken code
	cdate	Wed Nov 14 13:02:02 JST 2012
	who	msaitoh
	file	lib/libc/softfloat/Makefile.inc
	pr	46953
	regress	src/tests/lib/libm/t_cbrt
	regress	src/tests/lib/libm/t_ceil
	regress	src/tests/lib/libm/t_exp
	regress	src/tests/lib/libm/t_log
	regress	src/tests/lib/libm/t_scalbn
	regress	src/tests/lib/libm/t_sinh
	regress	src/tests/lib/libm/t_sqrt
	descr	Gcc has a bug in tree optimization. For adddf3,
		-INF + -INF returns 0 without -fno-tree-vrp.
		Debugging with -fdump-tree-all shows that
		softfloat.c.021t.cleanup_cfg is ok but softfloat.c.023t.ssa
		is broken.

port	sh3

	hack	gcc4-sh3-bz2
	cdate	Sun May 21 03:34:57 UTC 2006
	mdate	Fri May 16 13:13:00 UTC 2008
	who	mrg, tsutsui
	file	lib/libbz2/Makefile	: 1.10
		The in-tree GCC 4.1-based compiler generated too-far
		pc-relative addresses.  Hack is to build with

port	m68000

	hack	gcc4-m68000
	cdate	Fri Feb  8 10:29:37 PST 2008
	mdate	Sun May  4 15:37:19 UTC 2008
	who	mrg, tsutsui
	file	rescue/Makefile	: 1.21
	file	sbin/dump_lfs/Makefile	: 1.9
	file	sbin/fsck_ffs/Makefile	: 1.35
	file	sbin/fsdb/Makefile	: 1.22
	file	share/mk/sys.mk	: 1.96
	file	usr.sbin/ndbootd/Makefile	: 1.5
		Several internal compiler errors with gcc -O1
		around 64bit integer arithmetic.
		This hack uses -O1 and adds some -fno-tree-foo options
		to avoid the problem.
		This might be related with GCC Bugzilla Bug 32424.

port	m68k,sh3,vax

	hack	gcc-4.8.1
	cdate	Wed Nov  6 20:41:35 EST 2013
	who	christos
	file	src/external/gpl3/gcc/libstdc++-v3/Makefile : 1.6
		compile hashtable_c++0x.cc with -O2 instead of -Os to
		produce missing instantiation of std::lower_bound expansion
		for unsigned long.

port	sparc

	hack	avoid NULL pointer derefs in savefpstate IPIs and GCC 4.5.3
	cdate	Sun Aug 14 19:26:48 PDT 2011
	who	mrg
	file	sys/arch/sparc64/sparc/cpu.c : 1.234
	file	sys/arch/sparc64/sparc/cpuvar.h : 1.90
	file	sys/arch/sparc64/sparc/genassym.cf : 1.67
	file	sys/arch/sparc64/sparc/locore.s : 1.265
		Something is wrong with GCC 4.5.3 and the savefpstate IPI.
		Post newlock2 there was a bug where a lock was reduced from
		IPL_SCHED to IPL_VM (?) and occasionally savefpstate IPI
		would crash due to NULL IPI.  This was fixed by re-using the
		right IPL value.  However, GCC 4.5.3 build kernels have the
		same problems.  For now, the hack is re-instated.

port	mips

	hack	mips-shared-linker-load-address
	cdate	Fri Oct  7 08:33:10 UTC 2005
	who	simonb
	file	src/sys/kern/exec_elf32.c : 1.107
		With COMPAT_16 or previous enabled (which enables
		ELF_INTERP_NON_RELOCATABLE) a recent ld.elf_so will
		load and run at address 0.  The check to fix this in
		rev 1.107 only checks the first psection of the ELF
		executable, which may not be loadable.  A more correct
		fix is to check the first loadable psection instead of
		just the first psection.

	hack	mips-duplicate-ras-end-label
	cdate	Sat Sep  2 23:29:42 2006
	who	martin
	file	src/regress/sys/kern/ras/ras3/Makefile : 1.3
		Add -fno-reorder-blocks to CFLAGS to avoid duplicate
		labels by duplicated __asm output from RAS_END()

	hack	mips-mcount-assembler-warning
	cdate	Tue Jul 29 14:16:52 UTC 2008
	who	lukem
	file	src/lib/libc/gmon/Makefile.inc : 1.8
		Workaround for PR port-mips/39192.
		common/lib/libc/gmon/mcount.c generates a (fatal)
		assembler warning on MIPS:
			Warning: No .cprestore pseudo-op used in PIC code
		Add COPTS.count.c+=-Wa,--no-warn to avoid -Wa,--fatal-warnings

port	i386

	hack	use volatile intermediate variable to enforce rounding
	cdate	Tue Aug  1 22:15:55 MEST 2006
	who	drochner
	file	src/lib/libm/src/lrintf.c : 1.4
	file	src/lib/libm/src/s_rintf.c : 1.8
		gcc-4 does subsequent operations on "float" values within
		the i387 FPU without rounding the intermediate results

port	x86
	hack	turn off optimization for biosdisk_ll.c because otherwise
		we are pass the wrong arguments to biosdisk_read(). 
		$ cd /usr/src/sys/arch/i386/floppies/bootflopp-com
		$ qemu-system-i386 -nographic -fda boot-com1.fs -boot a
	who	christos
	file	src/sys/arch/i386/stand/lib/Makefile : 1.38
		Turning on DISK_DEBUG shows the problem. We should find
		out which option is causing this.

port	powerpc

	hack	avoid using __builtin_return_address(0) because it fails in
		Xorg's module loader
	cdate	Sat Sep 27 03:52:05 UTC 2008
	who	macallan
	file	src/libexec/ld.elf_so/rtld.c : 1.121
		workaround for PR port-macppc/37812

	hack	define TARGET_SECURE_PLT and HAVE_AS_TLS because when
		building the native compiler via build.sh those don't defined
	cdate	Sat Mar 12 08:00:00 UTC 2011
	who	matt
	file	src/gnu/dist/gcc4/gcc/config/rs6000/netbsd.h
		see above

port	powerpc64

	hack	include _errno.c in libposix so that __errno resolves. It
		should resolve from libc's errno, but somehow it does not.
		Linker bug?
	cdate	Thu Oct 27 13:19:47 EDT 2011
	who	christos
	file	src/lib/libposix/Makefile: 1.15
	file	src/lib/librt/Makefile: 1.14
		workaround for:
		    libposix_pic.a(cerror.pico)(.text+0x14): unresolvable \
		    R_PPC64_REL24 relocation against symbol `.__errno'

	hack	rename data() function in mdocml to avoid redefined error.
		Compiler/Assembler bug?
	cdate	Sat Oct 29 11:16:01 EDT 2011
	who	christos
	file	src/external/bsd/mdocml/tbl_data.c: 1.2
		workaround for:
		    {standard input}: Assembler messages:
		    {standard input}:105: Error: symbol `.data' is already \

port	emips

	hack	Add nop between ctc1 and mtc0 to avoid assembler internal
	cdate	Sat Oct 29 16:57:34 EDT 2011
	who	christos
	file	src/sys/arch/mips/mips/mips_fpu.c: 1.7
		workaround for:
		    {standard input}: Assembler messages:
		    {standard input}:730: Internal error!
		    Assertion failure in append_insn at /usr/src/external/gpl3/\
		    binutils/dist/gas/config/tc-mips.c line 2910.

port	ia64

	hack	libgcc unwind dummy function
	cdate	Fri Apr 17 14:31:03 CEST 2015
	who	martin
	file	src/external/gpl3/gcc/dist/libgcc/config/ia64/unwind-ia64.c: 1.4
		Add an empty _Unwind_FindTableEntry() implementation.
		In the end we will use our libc stuff, and this should
		go away again.

port	x68k

	hack	compiler error with gcc 4.5.x
	cdate	Fri May 24 13:23:01 EDT 2013
	who	christos
	file	src/external/gpl3/gcc/usr.bin/bakend/Makefile: 1.17
		xsrc/external/mit/xorg/lib/libGLU/Makefile: 1.11
		workaround for:
		internal compiler error: in cselib_record_set, at cselib.c:1999

hack	fallback to /usr/bin/clang-cpp in rpcgen
cdate	Wed Jun  5 15:49:27 CEST 2013
who	joerg
file	src/usr.bin/rpcgen/rpc_main.c
	It is undecided which compiler owns /usr/bin/cpp and whether it should
	exist in a MKGCC=no world. To allow rpcgen to work out-of-the-box,
	if either gcc or clang is installed, use /usr/bin/clang-cpp as fallback.
	This applies only if RPCGEN_CPP is not set and /usr/bin/cpp is not executable.

port	hppa

	hack	compiler error with gcc 4.5.x
	cdate	Tue Jul 23 07:42:28 BST 2013
	who	skrll
	file	src/sys/lib/libkern/Makefile.libkern: 1.26
		workaround for unanalysed codegen bug affecting md5c.c.

	hack	gdb vs _rtld_debug_state problem
	cdate	Thu Mar  5 09:49:53 UTC 2015
	who	skrll
	file	src/libexec/ld.elf_so/rtld.c: 1.175
		workaround for problem where gdb misses the breakpoint on
		_rtld_debug_state when the function is only the
		bv,n %r0(%rp) instruction - the nullify seems to
		confuse something

port	mips64*
hack	compiler crashes on mips64* with optimization enabled
cdate	Tue May 13 18:46:48 UTC 2014
who	macallan
file	src/external/lgpl3/gmp/lib/libgmp/arch/mips64eb/Makefile.inc: 1.6
	src/external/lgpl3/gmp/lib/libgmp/arch/mips64eb/config.h: 1.5
	src/external/lgpl3/gmp/lib/libgmp/arch/mips64el/Makefile.inc: 1.6
	src/external/lgpl3/gmp/lib/libgmp/arch/mips64el/config.h: 1.5
descr	workaround for n32 gcc doing unaligned 64bit accesses when optimizing
pr	48696

port	vax
hack	compile boot with -O1
cdate	Sat May 24 09:40:58 CEST 2014
who	martin
file	src/sys/arch/vax/boot/boot/Makefile: 1.41
descr	/boot does not work when compiled with -O2 and gcc 4.8

port	arm
hack	avoid using labels in a 12-bit constant.
who	matt
file	crypto/external/bsd/openssl/lib/libcrypto/arch/arm/aes-armv4.S: 1.2
descr	workaround for clang misassembling an instruction

port	sparc64
hack	during profiling with -m32 (and ASLR) labels are not generated
who	christos
file	/cvsroot/src/crypto/external/bsd/heimdal/lib/libasn1/Makefile: 1.4
desc 	asn1_krb5_asn1.po does not produce the same results during successive
	compilation runs; it is bimodal. Turning optimization to -O0 fixes
	the issue

port	ia64
hack	ski emulator crashes
who	scole
file	/cvsroot/src/sys/external/bsd/acpica/dist/tables/tbxfload.c: 1.6
	ski emulator crashes during acpi detection.  Added a check for
	uninitialized index.  Submitted a request for change with upstream
	mailing list, but never got a response

port	vax
hack	compile rtld.c with -O0
cdate	Wed Apr  3 17:38:38 EDT 2019
who	christos
file	src/libexec/ld.elf_so/Makefile: 1.141
descr	Disable optimization for rtld.c on the vax with gcc-7. Crashes on the
	second pass loop with elm == 0xffffffff

port	alpha
hack	GCC 7.4/8.3: userland binaries crash randomly (port-alpha/54307)
cdate	Fri Nov  1 20:43:35 UTC 2019
who	rin
file	src/external/bsd/jemalloc/lib/Makefile.inc: 1.11
descr	rtree.c and tcache.c need to be compiled with -O0, alternatively,
	you can compile whole jemalloc with -DJEMALLOC_DEBUG.