started here https://build.chromium.org/p/chromium.fyi/builders/ClangToTAndroidASan/builds/3365

FAILED: obj/mojo/public/cpp/bindings/bindings/multiplex_router.o 
../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/mojo/public/cpp/bindings/bindings/multiplex_router.o.d -DV8_DEPRECATION_WARNINGS -DENABLE_NOTIFICATIONS -DENABLE_BROWSER_CDMS -DENABLE_PRINTING=1 -DENABLE_BASIC_PRINTING=1 -DENABLE_SPELLCHECK=1 -DUSE_BROWSER_SPELLCHECKER=1 -DUSE_OPENSSL_CERTS=1 -DNO_TCMALLOC -DMEMORY_TOOL_REPLACES_ALLOCATOR -DMEMORY_SANITIZER_INITIAL_SIZE -DADDRESS_SANITIZER -DUSE_EXTERNAL_POPUP_MENU=1 -DENABLE_WEBRTC=1 -DDISABLE_NACL -DENABLE_SUPERVISED_USERS=1 -DVIDEO_HOLE=1 -DSAFE_BROWSING_DB_REMOTE -DCHROMIUM_BUILD -DENABLE_MEDIA_ROUTER=1 -DENABLE_WEBVR -DFIELDTRIAL_TESTING_ENABLED -DCR_CLANG_REVISION=273555 -D_FILE_OFFSET_BITS=64 -DANDROID -DHAVE_SYS_UIO_H -DANDROID_NDK_VERSION=r10e -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -DCOMPONENT_BUILD -D__GNU_SOURCE=1 -D__compiler_offsetof=__builtin_offsetof -Dnan=__builtin_nan -D_DEBUG -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DWTF_USE_DYNAMIC_ANNOTATIONS=1 -I../.. -Igen -fno-strict-aliasing --param=ssp-buffer-size=4 -fstack-protector -funwind-tables -fPIC -pipe -fcolor-diagnostics -ffunction-sections -fno-short-enums --target=arm-linux-androideabi -march=armv7-a -mfloat-abi=softfp -mthumb -mtune=generic-armv7-a -mfpu=neon -Wall -Werror -Wextra -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-nonportable-include-path -Wno-undefined-var-template -Os -fdata-sections -ffunction-sections -g1 --sysroot=../../third_party/android_tools/ndk/platforms/android-16/arch-arm -gline-tables-only -fno-omit-frame-pointer -fsanitize=address -fsanitize-blacklist=../../tools/memory/asan/blacklist.txt -mllvm -asan-globals=0 -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -fno-threadsafe-statics -fvisibility-inlines-hidden -Wno-undefined-bool-conversion -Wno-tautological-undefined-compare -std=gnu++11 -fno-rtti -isystem../../third_party/android_tools/ndk/sources/cxx-stl/llvm-libc++/libcxx/include -isystem../../third_party/android_tools/ndk/sources/cxx-stl/llvm-libc++abi/libcxxabi/include -isystem../../third_party/android_tools/ndk/sources/android/support/include -fno-exceptions -c ../../mojo/public/cpp/bindings/lib/multiplex_router.cc -o obj/mojo/public/cpp/bindings/bindings/multiplex_router.o

# In Register Scavenger
# Machine code for function _ZN4mojo8internal15MultiplexRouter22ProcessIncomingMessageEPNS_7MessageENS1_18ClientCallBehaviorEPN4base22SingleThreadTaskRunnerE: Properties: <Post SSA, tracking liveness, AllVRegsAllocated>
Frame Objects:
  fi#0: size=4, align=4, at location [SP-100]
  fi#1: variable sized, align=32, at location [SP-96]
  fi#2: size=4, align=4, at location [SP-104]
  fi#3: size=4, align=4, at location [SP-108]
  fi#4: size=4, align=4, at location [SP-112]
  fi#5: size=4, align=4, at location [SP-116]
  fi#6: size=4, align=4, at location [SP-120]
  fi#7: size=4, align=4, at location [SP-124]
  fi#8: size=4, align=4, at location [SP-128]
  fi#9: size=4, align=4, at location [SP-132]
  fi#10: size=4, align=4, at location [SP-136]
  fi#11: size=4, align=4, at location [SP-4]
  fi#12: size=4, align=4, at location [SP-8]
  fi#13: size=4, align=4, at location [SP-12]
  fi#14: size=4, align=4, at location [SP-16]
  fi#15: size=4, align=4, at location [SP-20]
  fi#16: size=4, align=4, at location [SP-24]
  fi#17: size=4, align=4, at location [SP-28]
  fi#18: size=4, align=4, at location [SP-32]
  fi#19: size=4, align=4, at location [SP-36]
Constant Pool:
  cp#0: __stack_chk_guard(GOT_PREL)-(LPC1+4-.), align=4
  cp#1: __asan_option_detect_stack_use_after_return(GOT_PREL)-(LPC0+4-.), align=4
  cp#2: __asan_gen_.71-(LPC3+4), align=4
  cp#3: _ZN4mojo8internal15MultiplexRouter22ProcessIncomingMessageEPNS_7MessageENS1_18ClientCallBehaviorEPN4base22SingleThreadTaskRunnerE-(LPC2+4), align=4
  cp#4: .str-(LPC5+4), align=4
  cp#5: .str.17-(LPC4+4), align=4
  cp#6: .str-(LPC7+4), align=4
  cp#7: .str.12-(LPC6+4), align=4
  cp#8: .str-(LPC9+4), align=4
  cp#9: .str.18-(LPC8+4), align=4
  cp#10: __stack_chk_guard(GOT_PREL)-(LPC10+4-.), align=4
Function Live Ins: %R0, %R1, %R2, %R3


last good clang 273532 first bad 273555