https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Ftryserver.chromium.mac%2Fmac_chromium_rel_ng%2F413426%2F%2B%2Frecipes%2Fsteps%2Fcompile__with_patch_%2F0%2Fstdout

FAILED: obj/third_party/WebKit/Source/core/html/html_2/ImageDocument.o 
export DEVELOPER_DIR=/b/c/b/mac/src/build/mac_files/Xcode.app;  /b/c/goma_client/gomacc ../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/third_party/WebKit/Source/core/html/html_2/ImageDocument.o.d -DV8_DEPRECATION_WARNINGS -DDCHECK_ALWAYS_ON=1 -DNO_TCMALLOC -DFULL_SAFE_BROWSING -DSAFE_BROWSING_CSD -DSAFE_BROWSING_DB_LOCAL -DCHROMIUM_BUILD -DENABLE_MEDIA_ROUTER=1 -DFIELDTRIAL_TESTING_ENABLED -DCR_CLANG_REVISION=\"296321-1\" -DCR_XCODE_VERSION=0511 -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_FORTIFY_SOURCE=2 -D__ASSERT_MACROS_DEFINE_VERSIONS_WITHOUT_UNDERSCORE=0 -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DBLINK_CORE_IMPLEMENTATION=1 -DBLINK_IMPLEMENTATION=1 -DINSIDE_BLINK -DSK_IGNORE_DW_GRAY_FIX -DSK_IGNORE_DIRECTWRITE_GASP_FIX -DSK_IGNORE_LINEONLY_AA_CONVEX_PATH_OPTS -DSK_SUPPORT_GPU=1 -DSK_BUILD_FOR_MAC -DENABLE_LAYOUT_UNIT_IN_INLINE_BOXES=0 -DENABLE_OILPAN=1 -DWTF_USE_CONCATENATED_IMPULSE_RESPONSES=1 -DU_USING_ICU_NAMESPACE=0 -DU_ENABLE_DYLOAD=0 -DU_STATIC_IMPLEMENTATION -DICU_UTIL_DATA_IMPL=ICU_UTIL_DATA_FILE -DANGLE_ENABLE_RELEASE_ASSERTS -DLIBXSLT_STATIC -I../.. -Igen -I../../third_party/WebKit/Source/platform -I../../third_party/WebKit/Source -I../../third_party/WebKit -Igen/blink -Igen/third_party/WebKit -I../../third_party/khronos -I../../gpu -I../../third_party/libwebp -I../../third_party/WebKit/Source -Igen/blink -I../../skia/config -I../../skia/ext -I../../third_party/skia/include/c -I../../third_party/skia/include/config -I../../third_party/skia/include/core -I../../third_party/skia/include/effects -I../../third_party/skia/include/images -I../../third_party/skia/include/lazy -I../../third_party/skia/include/pathops -I../../third_party/skia/include/pdf -I../../third_party/skia/include/pipe -I../../third_party/skia/include/ports -I../../third_party/skia/include/utils -I../../third_party/skia/include/gpu -I../../third_party/skia/src/gpu -I../../third_party/skia/src/sksl -I../../third_party/icu/source/common -I../../third_party/icu/source/i18n -I../../third_party/angle/include -I../../third_party/angle/src/common/third_party/numerics -Igen/angle -I../../third_party/iccjpeg -I../../third_party/libpng -I../../third_party/zlib -I../../third_party/libxml/src/include -I../../third_party/libxml/mac/include -I../../third_party/libxslt -I../../third_party/ots/include -I../../third_party/snappy/src -I../../third_party/snappy/mac -I../../v8/include -Igen/v8/include -fno-strict-aliasing -fstack-protector -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -fcolor-diagnostics -arch x86_64 -Wall -Werror -Wextra -Wpartial-availability -Wno-missing-field-initializers -Wno-unused-parameter -Wno-c++11-narrowing -Wno-covered-switch-default -Wno-deprecated-register -Wno-unneeded-internal-declaration -Wno-inconsistent-missing-override -Wno-shift-negative-value -Wno-undefined-var-template -Wno-nonportable-include-path -Wno-address-of-packed-member -Wno-unused-lambda-capture -Wno-user-defined-warnings -O2 -g1 -isysroot /b/c/b/mac/src/build/mac_files/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk -mmacosx-version-min=10.9 -fvisibility=hidden -Xclang -load -Xclang ../../third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.dylib -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang check-auto-raw-pointer -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Wexit-time-destructors -Xclang -load -Xclang ../../third_party/llvm-build/Release+Asserts/lib/libBlinkGCPlugin.dylib -Xclang -add-plugin -Xclang blink-gc-plugin -Xclang -plugin-arg-blink-gc-plugin -Xclang warn-stack-allocated-trace-method -Wglobal-constructors -DLIBXML_STATIC= -fvisibility-inlines-hidden -std=c++11 -stdlib=libc++ -fno-rtti -fno-exceptions -include obj/third_party/WebKit/Source/core/html/html_2/Prefix.h-cc -c ../../third_party/WebKit/Source/core/html/ImageDocument.cpp -o obj/third_party/WebKit/Source/core/html/html_2/ImageDocument.o
<built-in>:1:10: fatal error: 'obj/third_party/WebKit/Source/core/html/html_2/Prefix.h-cc' file not found
#include "obj/third_party/WebKit/Source/core/html/html_2/Prefix.h-cc"
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.


It looks like mac_precompiled_headers is active even if is_goma is true, which is a bug. Still strange that this usually works.