Started here: https://ci.chromium.org/buildbot/chromium.clang/ToTLinux%20%28dbg%29/2517

FAILED: gpu_unittests 
python "../../build/toolchain/gcc_link_wrapper.py" --output="./gpu_unittests" -- ../../third_party/llvm-build/Release+Asserts/bin/clang++ -fPIC -Wl,-z,noexecstack -Wl,-z,now -Wl,-z,relro -Wl,-z,defs -Wl,--no-as-needed -lpthread -Wl,--as-needed -fuse-ld=lld -Wl,--icf=all -m64 -Werror -Wl,--gdb-index -Wl,--fatal-warnings -nostdlib++ --sysroot=../../build/linux/debian_sid_amd64-sysroot -L../../build/linux/debian_sid_amd64-sysroot/usr/local/lib/x86_64-linux-gnu -Wl,-rpath-link=../../build/linux/debian_sid_amd64-sysroot/usr/local/lib/x86_64-linux-gnu -L../../build/linux/debian_sid_amd64-sysroot/lib/x86_64-linux-gnu -Wl,-rpath-link=../../build/linux/debian_sid_amd64-sysroot/lib/x86_64-linux-gnu -L../../build/linux/debian_sid_amd64-sysroot/usr/lib/x86_64-linux-gnu -Wl,-rpath-link=../../build/linux/debian_sid_amd64-sysroot/usr/lib/x86_64-linux-gnu -Wl,-rpath-link=. -Wl,--disable-new-dtags -Wl,-rpath=\$ORIGIN/. -Wl,-rpath-link=. -Wl,--export-dynamic -o "./gpu_unittests" -Wl,--start-group @"./gpu_unittests.rsp" ./libgles2.so ./libgpu.so ./libbase.so ./libcc_paint.so ./libviz_resource_format.so ./libgles2_c_lib.so ./libgles2_implementation.so ./libgles2_utils.so ./libgl_in_process_context.so ./libgpu_ipc_service.so ./libmojo_edk.so ./libbindings.so ./libskia.so ./libgfx.so ./libgeometry.so ./libgl_wrapper.so ./liburl.so ./libmojo_public_system_cpp.so ./libmojo_public_system.so ./libcolor_space.so ./libgeometry_skia.so ./libgfx_switches.so ./libicui18n.so ./libicuuc.so ./libanimation.so ./libcodec.so ./librange.so ./libcrash_key.so ./libipc.so ./libmessage_support.so ./libipc_mojom.so ./libipc_mojom_shared.so ./libbindings_base.so ./libmojo_mojom_bindings.so ./libmojo_mojom_bindings_shared.so ./libprotobuf_lite.so ./libgfx_ipc.so ./libgfx_ipc_geometry.so ./liburl_ipc.so ./libui_base.so ./libui_data_pack.so ./libevents_base.so ./libplatform.so ./libkeycodes_x11.so ./libui_base_x.so ./libdisplay.so ./libdisplay_types.so ./libgl_init.so ./libbase_i18n.so ./libfontconfig.so ./libx11_window.so ./libcc_base.so ./libcc_debug.so ./libraster.so ./libgpu_util.so ./libmojo_base_mojom_shared.so ./libmojo_base_mojom.so ./libmojo_base_lib.so ./libmojo_base_shared_typemap_traits.so ./libgfx_ipc_color.so ./libnet.so ./libcrcrypto.so ./libboringssl.so ./libmojo_edk_ports.so ./libnet_with_v8.so ./libfreetype_harfbuzz.so ./libc++.so -Wl,--end-group   -ldl -lpthread -lrt -lgmodule-2.0 -lgobject-2.0 -lgthread-2.0 -lglib-2.0 -lnss3 -lnssutil3 -lsmime3 -lplds4 -lplc4 -lnspr4 -lX11 -lX11-xcb -lxcb -lXcomposite -lXcursor -lXdamage -lXext -lXfixes -lXi -lXrender -lXtst 
/b/c/b/ToTLinux__dbg_/src/out/Debug/../../third_party/llvm-build/Release+Asserts/bin/ld.lld: error: undefined symbol: gpu::gles2::ClientServiceMap<unsigned long, unsigned long>::kMaxFlatArraySize
>>> referenced by client_service_map_unittest.cc:159 (../../gpu/command_buffer/service/client_service_map_unittest.cc:159)
>>>               obj/gpu/gpu_unittests/client_service_map_unittest.o:(gpu::gles2::ClientServiceMap_ForEach_Test::TestBody())
clang-7: error: linker command failed with exit code 1 (use -v to see invocation)


The pinned bots are happy and there's no client_service code change, so probably an lld regression.

First bad: 329319
Last good: 329291

`svn log -r329292:329319 https://nico@llvm.org/svn/llvm-project`

Hm, that does include "r329300; Disable -fmerge-all-constants as default." which might be related. The rest looks pretty harmless. Since we want to add that flag explicitly anyhow, we should probably just try adding it on the tot bots and see if it helps.



(cc ruiu for this tangent: I find lld error output hard to read somehow. One, why does it print the name of itself in front of errors? Two, if it must do that (clang doesn't; and the build system usually prints what step failed), maybe just the basename is enough. With that:

error: undefined symbol: gpu::gles2::ClientServiceMap<unsigned long, unsigned long>::kMaxFlatArraySize
>>> referenced by client_service_map_unittest.cc:159 (../../gpu/command_buffer/service/client_service_map_unittest.cc:159)
>>>               obj/gpu/gpu_unittests/client_service_map_unittest.o:(gpu::gles2::ClientServiceMap_ForEach_Test::TestBody())

Then, why print ">>>" instead of just whitespace?

error: undefined symbol: gpu::gles2::ClientServiceMap<unsigned long, unsigned long>::kMaxFlatArraySize
    referenced by client_service_map_unittest.cc:159 (../../gpu/command_buffer/service/client_service_map_unittest.cc:159)
                  obj/gpu/gpu_unittests/client_service_map_unittest.o:(gpu::gles2::ClientServiceMap_ForEach_Test::TestBody())

Also, it might be nice to not print "error: hi.obj: undefined symbol:" for each undefined symbol, but instead do:

error: undefined symbols:
  gpu::gles2::ClientServiceMap<unsigned long, unsigned long>::kMaxFlatArraySize, referenced by
      client_service_map_unittest.cc:159 (../../gpu/command_buffer/service/client_service_map_unittest.cc:159)
      obj/gpu/gpu_unittests/client_service_map_unittest.o:(gpu::gles2::ClientServiceMap_ForEach_Test::TestBody())
  next undefined symbol if there's more than one


I'd find each of these steps a big improvement in lld output readability. Also, it looks like lld-link doesn't print the "referenced by" bit (?). Probably should file different bugs for this...)