After landing bug 1163171, it causes the following build error on my workstation. 0:02.62 Executing: /home/makoto/.mozbuild/android-ndk-r15c/toolchains/llvm/preb uilt/linux-x86_64/bin/clang++ -std=gnu++11 --target=arm-linux-androideabi -Qunus ed-arguments -isystem /home/makoto/.mozbuild/android-ndk-r15c/platforms/android- 9/arch-arm/usr/include -gcc-toolchain /home/makoto/.mozbuild/android-ndk-r15c/to olchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64 -Qunused-arguments -Wal l -Wc++11-compat -Wempty-body -Wignored-qualifiers -Woverloaded-virtual -Wpointe r-arith -Wsign-compare -Wtype-limits -Wunreachable-code -Wunreachable-code-retur n -Wwrite-strings -Wno-invalid-offsetof -Wclass-varargs -Wloop-analysis -Wc++11- compat-pedantic -Wc++14-compat -Wc++14-compat-pedantic -Wc++1z-compat -Wcomma -W implicit-fallthrough -Wstring-conversion -Wno-inline-new-delete -Wno-error=depre cated-declarations -Wno-error=array-bounds -Wformat -Wno-gnu-zero-variadic-macro -arguments -Wformat-security -Wno-unknown-warning-option -Wno-return-type-c-link age -fno-short-enums -fno-exceptions -I/home/makoto/.mozbuild/android-ndk-r15c/s ources/cxx-stl/llvm-libc++/include -I/home/makoto/.mozbuild/android-ndk-r15c/sou rces/android/support/include -I/home/makoto/.mozbuild/android-ndk-r15c/sources/c xx-stl/llvm-libc++abi/include -march=armv7-a -mthumb -mfpu=vfp -mfloat-abi=softf p -mno-unaligned-access -fno-exceptions -fno-strict-aliasing -fno-rtti -fno-exce ptions -fno-math-errno -pipe -g -Oz -funwind-tables -fPIC -shared -Wl,-z,defs -W l,-h,libfakeopenh264.so -o libfakeopenh264.so /mozilla/objdir-android/dom/media/ gmp-plugin-openh264/tmpo6Qqvh.list -L/home/makoto/.mozbuild/android-ndk-r15c/pla tforms/android-9/arch-arm/usr/lib -Wl,-rpath-link=/home/makoto/.mozbuild/android -ndk-r15c/platforms/android-9/arch-arm/usr/lib --sysroot=/home/makoto/.mozbuild/ android-ndk-r15c/platforms/android-9/arch-arm -Wl,--allow-shlib-undefined -gcc-t oolchain /home/makoto/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideab i-4.9/prebuilt/linux-x86_64 -mthumb -Wl,-z,noexecstack -Wl,-z,text -Wl,-z,relro -Wl,--build-id -Wl,--hash-style=sysv -B ../../../build/unix/gold -Wl,-rpath-link ,/mozilla/objdir-android/dist/bin -Wl,-rpath-link,/usr/local/lib -fcolor-diagnos tics -L/home/makoto/.mozbuild/android-ndk-r15c/sources/cxx-stl/llvm-libc++/libs/ armeabi-v7a -lc++_static -lc++abi -lunwind -landroid_support -llog 0:02.62 /mozilla/objdir-android/dom/media/gmp-plugin-openh264/tmpo6Qqvh.list: 0:02.62 INPUT("gmp-fake-openh264.o") 0:02.62 0:02.62 ../../../build/unix/gold/ld: fatal error: /home/makoto/.mozbuild/androi d-ndk-r15c/platforms/android-9/arch-arm/usr/lib/../lib/crtbegin_so.o: unsupporte d ELF machine number 40 0:02.62 clang++: error: linker command failed with exit code 1 (use -v to see i nvocation)

reason maybe the following. ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin$ ./arm-linux-androideabi-gcc -print-prog-name=ld.gold /home/mkato/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld.gold ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin$ ./clang -print-prog-name=ld.gold /usr/bin/ld.gold

What does: ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin$ ./clang -gcc-toolchain ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/ -print-prog-name=ld.gold print for you?

Actually, better: ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin$ ./clang --target arm-linux-androideabi -gcc-toolchain ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/ -print-prog-name=ld.gold

(In reply to Nathan Froyd [:froydnj] from comment #4) > Actually, better: > > ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin$ > ./clang --target arm-linux-androideabi -gcc-toolchain > ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/ > linux-x86_64/ -print-prog-name=ld.gold And as reported by #mobile, the correct command should actually be (notice the --target= option): ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin$ ./clang --target=arm-linux-androideabi -gcc-toolchain ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/ -print-prog-name=ld.gold For me, I get: froydnj@hawkeye:~/src/gecko-dev.git$ /home/froydnj/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin/clang --target=arm-linux-androideabi -gcc-toolchain /home/froydnj/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/ -print-prog-name=ld.gold /home/froydnj/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld.gold which is correct (that file exists and knows how to link ARM object files). If the link command isn't finding that linker and is using the system linker instead, that is a problem.

To get correct name, it requires --target and -gcc-toolchain. makoto@breakbeat:/mozilla$ ~/.mozbuild/android-ndk-r15c/toolchains/llvm/prebuilt/linux-x86_64/bin/clang --target=arm-linux-androideabi -gcc-toolchain ~/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64 -print-prog-name=ld.gold /home/makoto/.mozbuild/android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld.gold http://searchfox.org/mozilla-central/rev/1ebd2eff44617df3b82eea7d2f3ca1b60cc591a0/build/moz.configure/toolchain.configure#1401-1402 gold_detection_arg = '-print-prog-name=ld.gold' gold = check_cmd_output(c_compiler.compiler, gold_detection_arg).strip() Maybe, this doesn't use --target and -gcc-toolchain

We were adding c_compiler.flags and toolchain_flags to some paths through this function, but not all. Not adding those flags caused this function to detect the host's ld.gold instead of the target's ld.gold. And that, in turn, caused linker errors when the host ld.gold couldn't understand the target's object files.

Pushed by nfroyd@mozilla.com: https://hg.mozilla.org/mozilla-central/rev/a89e5587c7a7 use the correct command-line flags to detect gold; r=snorp; a=RyanVM

Sorry about this breakage. :( I fixed this case for the automation builds, but because of my mozconfig, wasn't fixing it for developer builds.