When compiling chromium on ppc64 it runs the ./generate_gni.sh script: https://github.com/gentoo/gentoo/blob/master/www-client/chromium/chromium-107.0.5304.87.ebuild#L634 According to the wiki when compiling with clang (which is necessary unless you want it to be dead slow) you will force libunwind usage: https://wiki.gentoo.org/wiki/Chromium#Clang talos2 ~ # cat /etc/portage/env/compiler-clang LDFLAGS="${LDFLAGS} -fuse-ld=lld -rtlib=compiler-rt -unwindlib=libunwind -Wl,--as-needed" # Hardening _HARDENING_FLAGS="-fstack-protector-strong -D_FORTIFY_SOURCE=2" CFLAGS="${CFLAGS} ${_HARDENING_FLAGS}" CXXFLAGS="${CXXFLAGS} ${_HARDENING_FLAGS}" LDFLAGS="${LDFLAGS} -Wl,-z,relro,-z,now" CC="clang" CXX="clang++" AR="llvm-ar" NM="llvm-nm" RANLIB="llvm-ranlib" talos2 ~ # cat /etc/portage/env/clang-chromium # Optionally, add these to EXTRA_GN: # - thin_lto_enable_optimizations=true # - use_thin_lto=true # - is_cfi=true EXTRA_GN="use_lld=true is_clang=true clang_use_chrome_plugins=false" # # Needed with GCC 11 CHROMIUM_FORCE_LIBCXX=yes Unlike mesa, when compiling with clang chromium won't link against libunwind/llvm-libunwind, but it will still be required to run the ./generate_gni.sh script otherwise it fails: https://bugs.gentoo.org/669748#c45 Initially I didn't know why it was failing, but I've now tracked it down to the lack of libunwind/llvm-libunwind: emerging it fixes the issue. What I did notice before is that even though ./generate_gni.sh was failing, removing || die and letting it fail was not a problem and the build would succeed anyway. I'm not sure what would be the beast way to proceed: actually libunwind/llvm-libunwind is necessary only on ppc64 and only if you compile it with clang, but it doesn't link against it (maybe because -custom-cflags prevents it from being used?). Unfortunately ./generate_gni.sh still needs libunwind, but you can let it fail and it won't matter anyway.
