| Index: build/config/compiler/BUILD.gn
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| diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
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| index e6cc59b840a0dbaa45597a0a756074f720047eef..7aaa9fbe8b80fd420b0960578de9c7e81c169206 100644
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| --- a/build/config/compiler/BUILD.gn
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| +++ b/build/config/compiler/BUILD.gn
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| @@ -56,6 +56,11 @@ declare_args() {
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|      # The patch is preapplied to the internal toolchain and hence all bots.
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|      msvs_xtree_patched = false
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|    }
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| +
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| +  # Track where uninitialized memory originates from. From fastest to slowest:
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| +  # 0 - no tracking, 1 - track only the initial allocation site, 2 - track the
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| +  # chain of stores leading from allocation site to use site.
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| +  msan_track_origins = 2
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|  }
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|  
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|  # default_include_dirs ---------------------------------------------------------
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| @@ -139,12 +144,39 @@ config("compiler") {
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|        ]
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|      }
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|      if (is_asan) {
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| -      cflags += [ "-fsanitize=address" ]
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| +      asan_blacklist_path =
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| +          rebase_path("//tools/memory/asan/blacklist.txt", root_build_dir)
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| +      cflags += [
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| +        "-fsanitize=address",
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| +        "-fsanitize-blacklist=$asan_blacklist_path",
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| +      ]
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|        if (is_mac) {
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|          cflags += [ "-mllvm -asan-globals=0" ]  # http://crbug.com/352073
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|          # TODO(GYP): deal with mac_bundles.
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|        }
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|      }
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| +    if (is_lsan) {
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| +      cflags += [ "-fsanitize=leak" ]
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| +    }
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| +    if (is_tsan) {
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| +      tsan_blacklist_path =
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| +          rebase_path("//tools/memory/tsan_v2/ignores.txt", root_build_dir)
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| +      cflags += [
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| +        "-fsanitize=thread",
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| +        "-fsanitize-blacklist=$tsan_blacklist_path",
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| +      ]
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| +    }
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| +    if (is_msan) {
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| +      msan_blacklist_path =
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| +          rebase_path("//tools/msan/blacklist.txt", root_build_dir)
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| +      cflags += [
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| +        "-fsanitize=memory",
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| +        "-fsanitize-memory-track-origins=$msan_track_origins",
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| +        "-fsanitize-blacklist=$msan_blacklist_path",
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| +      ]
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| +
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| +      # TODO(GYP): Support instrumented libraries and custom libc++.
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| +    }
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|    }
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|  
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|    if (is_clang && is_debug) {
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| 
 |