thakis@, what do you think about adding COMPILER_CLANG to build/build_config.h?

third_party/WebKit/Source/platform/wtf/Compiler.h has WTF_COMPILER_CLANG/MSVC/GCC. bulid_config.h has only COMPILER_GCC/MSVC.

I don't think we need to add it. We've made it for years without it, so I don't think it should be necessary. Most of the time if you check for gcc and msvc in the right way (clang can identify itself as either, depending on which platform it targets) you won't need an explicit clang check. And if you do, you can check for __clang__.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2b69815dba958ed45692284ce857698f00362db0

commit 2b69815dba958ed45692284ce857698f00362db0
Author: Kent Tamura <tkent@chromium.org>
Date: Mon Jul 03 05:43:53 2017

Remove COMPILER(CLANG).

Use defined(__clang__) directly instead.  We didn't have many usage of
COMPILER(CLANG), and Chromium doesn't have COMPILER_CLANG.

This is a preparation to remove COMPILER() macro.

Bug:  738337 
Change-Id: Ib39509c228b475b55284e44f5317d1c2eed4fa96
Reviewed-on: https://chromium-review.googlesource.com/558327
Commit-Queue: Yuta Kitamura <yutak@chromium.org>
Reviewed-by: Yuta Kitamura <yutak@chromium.org>
Cr-Commit-Position: refs/heads/master@{#483948}
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/templates/interface.cpp.tmpl
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/templates/legacy_callback_interface.cpp.tmpl
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8ArrayBuffer.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8ArrayBufferView.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8DataView.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8SVGTestInterface.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestCallbackFunctions.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestConstants.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestIntegerIndexed.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestIntegerIndexedGlobal.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestIntegerIndexedPrimaryGlobal.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterface.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterface2.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterface3.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceCheckSecurity.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceConstructor.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceConstructor2.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceConstructor3.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceConstructor4.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceCustomConstructor.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceDocument.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceEmpty.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceEventInitConstructor.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceEventTarget.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceGarbageCollected.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceNamedConstructor.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceNamedConstructor2.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceNode.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceOriginTrialEnabled.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestInterfaceSecureContext.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestLegacyCallbackInterface.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestNode.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestObject.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestSpecialOperations.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestSpecialOperationsNotEnumerable.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8TestTypedefs.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/core/V8Uint8ClampedArray.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/modules/V8TestInterface5.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/bindings/tests/results/modules/V8TestSubObject.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/WebTaskRunnerTest.cpp
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/heap/GarbageCollected.h
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/wtf/Allocator.h
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/wtf/Compiler.h
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/wtf/TypeTraits.h
[modify] https://crrev.com/2b69815dba958ed45692284ce857698f00362db0/third_party/WebKit/Source/platform/wtf/TypeTraitsTest.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1b88eef89bc4de302c51329bdf1f1c3bbcec9050

commit 1b88eef89bc4de302c51329bdf1f1c3bbcec9050
Author: Kent Tamura <tkent@chromium.org>
Date: Mon Jul 03 10:10:46 2017

Remove COMPILER() macro.

Use defined(COMPILER_FOO) instead.

Bug:  738337 
Change-Id: I8e37239483589c6b99aff8ea11561faa8766bc1b
Reviewed-on: https://chromium-review.googlesource.com/558826
Commit-Queue: Yuta Kitamura <yutak@chromium.org>
Reviewed-by: Yuta Kitamura <yutak@chromium.org>
Cr-Commit-Position: refs/heads/master@{#483975}
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/core/CoreExport.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/core/dom/Attribute.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/core/dom/ElementData.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/core/html/parser/MarkupTokenizerInlines.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/core/svg/SVGPathByteStreamSource.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteDatabase.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/audio/DenormalDisabler.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/bindings/ScriptWrappable.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/fonts/WebFontDecoder.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/graphics/Color.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/heap/Heap.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/heap/HeapAllocator.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/heap/HeapPage.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/heap/StackFrameDepth.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/Alignment.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/Assertions.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/Atomics.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/ByteSwap.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/Compiler.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/DateMath.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/HashFunctions.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/MathExtras.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/StackUtil.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/StackUtil.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/StdLibExtras.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/StringExtras.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/TypeTraits.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/TypeTraitsTest.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/Vector.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/WTFThreadData.cpp
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/WTFThreadData.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/text/ASCIIFastPath.h
[modify] https://crrev.com/1b88eef89bc4de302c51329bdf1f1c3bbcec9050/third_party/WebKit/Source/platform/wtf/text/StringOperatorsTest.cpp