Created attachment 438022 [details] Build log seamonkey-2.40 fails to build on PPC with gcc-4.9.3, it fails when linking libxul.so, with undefined references to __atomic_*, like eg.: Unified_cpp_media_mediasource0.cpp:(.text._ZN7mozilla6detail18IntrinsicMemoryOpsIxLNS_14MemoryOrderingE2EE4loadERKSt6atomicIxE[_ZN7mozilla6detail18IntrinsicMemoryOpsIxLNS_14MemoryOrderingE2EE4loadERKSt6atomicIxE]+0x24): undefined reference to `__atomic_load_8' It seems that programs using std::atomic with this compiler need an additional -latomic LDFLAG For example, with the following test program: ~~~ #include <atomic> struct A { unsigned long a; unsigned long b; }; struct B { void set (A tmp) { _a.store (tmp); } std::atomic<A> _a; }; int main () { B b; b.set (A ()); return 0; } ~~~ $ g++ -o test test.cpp -std=c++11 /tmp/ccuqxPRX.o: In function `std::atomic<A>::store(A, std::memory_order)': test.cpp:(.text._ZNSt6atomicI1AE5storeES0_St12memory_order[_ZNSt6atomicI1AE5storeES0_St12memory_order]+0x4c): undefined reference to `__atomic_store_8' collect2: error: ld returned 1 exit status $ g++ -o test test.cpp -std=c++11 -latomic ... builds fine ... emerge -pqv: [ebuild N ] www-client/seamonkey-2.40 USE="chatzilla crypt dbus gmp-autoupdate gstreamer ipc jemalloc3 jit roaming startup-notification -custom-cflags -custom-optimization -debug -gstreamer-0 -minimal (-neon) -pulseaudio (-selinux) -system-cairo -system-icu -system-jpeg -system-libvpx -system-sqlite {-test} -wifi" LINGUAS="-be -ca -cs -de -en_GB -es_AR -es_ES -fi -fr -gl -hu -it -ja -lt -nb_NO -nl -pl -pt_PT -ru -sk -sv_SE -tr -uk -zh_CN -zh_TW" emerge --info: Portage 2.2.26 (python 3.4.3-final-0, default/linux/powerpc/ppc32/13.0/desktop, gcc-4.9.3, glibc-2.22-r4, 4.1.15-gentoo-r1 ppc) ================================================================= System Settings ================================================================= System uname: Linux-4.1.15-gentoo-r1-ppc-7450,_altivec_supported-with-gentoo-2.2 KiB Mem: 767140 total, 515212 free KiB Swap: 3021788 total, 3011600 free Timestamp of repository gentoo: Thu, 16 Jun 2016 03:00:01 +0000 sh bash 4.3_p42-r1 ld GNU ld (Gentoo 2.25.1 p1.1) 2.25.1 app-shells/bash: 4.3_p42-r1::gentoo dev-lang/perl: 5.20.2::gentoo dev-lang/python: 2.7.10-r1::gentoo, 3.4.3-r1::gentoo dev-util/cmake: 3.3.1-r1::gentoo dev-util/pkgconfig: 0.28-r2::gentoo sys-apps/baselayout: 2.2::gentoo sys-apps/openrc: 0.19.1::gentoo sys-apps/sandbox: 2.10-r1::gentoo sys-devel/autoconf: 2.13::gentoo, 2.69::gentoo sys-devel/automake: 1.11.6-r1::gentoo, 1.14.1::gentoo, 1.15::gentoo sys-devel/binutils: 2.25.1-r1::gentoo sys-devel/gcc: 4.9.3::gentoo sys-devel/gcc-config: 1.7.3::gentoo sys-devel/libtool: 2.4.6::gentoo sys-devel/make: 4.1-r1::gentoo sys-kernel/linux-headers: 4.3::gentoo (virtual/os-headers) sys-libs/glibc: 2.22-r4::gentoo Repositories: gentoo location: /usr/portage sync-type: rsync sync-uri: rsync://rsync.gentoo.org/gentoo-portage priority: -1000 ACCEPT_KEYWORDS="ppc" ACCEPT_LICENSE="* -@EULA" CBUILD="powerpc-unknown-linux-gnu" CFLAGS="-mcpu=7450 -mtune=7450 -O2 -maltivec -mabi=altivec -fno-strict-aliasing -pipe" CHOST="powerpc-unknown-linux-gnu" CONFIG_PROTECT="/etc /usr/share/gnupg/qualified.txt" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/dconf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/sandbox.d /etc/terminfo" CXXFLAGS="-mcpu=7450 -mtune=7450 -O2 -maltivec -mabi=altivec -fno-strict-aliasing -pipe" DISTDIR="/usr/portage/distfiles" FCFLAGS="-O2 -pipe" FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr" FFLAGS="-O2 -pipe" GENTOO_MIRRORS="ftp://tux.rainside.sk/gentoo/ ftp://gentoo.wheel.sk/pub/linux/gentoo/" LANG="en_US.utf8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j2" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" USE="X a52 aac acl alsa altivec berkdb bluetooth branding bzip2 cairo cdda cdr cli consolekit cracklib crypt cups cxx dbus dri dts dvd dvdr emboss encode exif fam ffmpeg firefox flac fortran gdbm gif glamor gpm gtk gtk2 iconv ipv6 jpeg lcms ldap libnotify mad mng modules mp3 mp4 mpeg ncurses nls nptl ogg opengl openmp pam pango pcre pdf png policykit ppc ppds qt3support readline sdl session spell ssl startup-notification svg tcpd theora tiff truetype udev udisks unicode upower usb vorbis wxwidgets x264 xattr xcb xml xv xvid zlib" ABI_PPC="32" ALSA_CARDS="aoa aoa-fabric-layout aoa-onyx aoa-soundbus aoa-soundbus-i2s aoa-tas aoa-toonie powermac usb-audio via82xx" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-5" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_4" RUBY_TARGETS="ruby20 ruby21" USERLAND="GNU" VIDEO_CARDS="fbdev" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CC, CPPFLAGS, CTARGET, CXX, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON
Created attachment 438416 [details, diff] Patch that adds an autoconf check for whether -latomic is needed I've written a patch to add an autoconf check that determines whether -latmoic should be added to LIBS or not. The browser compiles and seems to work fine. It checks whether one can store a value into a std::atomic<double> variable without, and if unsuccessful with -latomic, and if that succeeds, it adds it to LIBS. Otherwise, it just prints a warning if neither way succeeds to link.
It's no longer an issue on seamonkey-2.42, a very similar autoconf check to the one I've provided here was added.
