From 502ce644e4a319e99d25602356895831ec16c033 Mon Sep 17 00:00:00 2001
From: Jose Dapena Paz <jose.dapena@lge.com>
Date: Wed, 7 Mar 2018 18:50:50 +0000
Subject: [PATCH 2/7] GCC build fix: mark is_trivially_copy_constructible for
 WTF::Vector as false.
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Compilation in GCC fails because of https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80654
if T in WTF::Optional<WTF::Vector<T>> is not trivially copy constructible.
The problem already happened in std::vector and was workarounded. This
change implements a similar fix for WTF::Vector.

Bug: 816952

Change-Id: If87f01beb952e03eb49dcaf0c5db6efd745bf05e
Reviewed-on: https://chromium-review.googlesource.com/944404
Commit-Queue: José Dapena Paz <jose.dapena@lge.com>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541516}
---
 third_party/WebKit/Source/platform/wtf/DEPS     |  1 +
 third_party/WebKit/Source/platform/wtf/Vector.h | 17 +++++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/third_party/WebKit/Source/platform/wtf/DEPS b/third_party/WebKit/Source/platform/wtf/DEPS
index a2b6603245b4..bccf1e08c77d 100644
--- a/third_party/WebKit/Source/platform/wtf/DEPS
+++ b/third_party/WebKit/Source/platform/wtf/DEPS
@@ -16,6 +16,7 @@ include_rules = [
     "+base/process/process_metrics.h",
     "+base/rand_util.h",
     "+base/strings",
+    "+base/template_util.h",
     "+base/threading/thread_checker.h",
     "+base/time/time.h",
     "+base/tuple.h",
diff --git a/third_party/WebKit/Source/platform/wtf/Vector.h b/third_party/WebKit/Source/platform/wtf/Vector.h
index c356287b2f42..8421b135e162 100644
--- a/third_party/WebKit/Source/platform/wtf/Vector.h
+++ b/third_party/WebKit/Source/platform/wtf/Vector.h
@@ -28,6 +28,7 @@
 #include <utility>
 
 #include "base/macros.h"
+#include "base/template_util.h"
 #include "build/build_config.h"
 #include "platform/wtf/Alignment.h"
 #include "platform/wtf/ConditionalDestructor.h"
@@ -1995,6 +1996,22 @@ Vector<T, inlineCapacity, Allocator>::Trace(VisitorDispatcher visitor) {
 
 }  // namespace WTF
 
+namespace base {
+
+#if defined(__GNUC__) && !defined(__clang__) && __GNUC__ <= 7
+// Workaround for g++7 and earlier family.
+// Due to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80654, without this
+// Optional<WTF::Vector<T>> where T is non-copyable causes a compile error.
+// As we know it is not trivially copy constructible, explicitly declare so.
+//
+// It completes the declaration in base/template_util.h that was provided
+// for std::vector
+template <typename T>
+struct is_trivially_copy_constructible<WTF::Vector<T>> : std::false_type {};
+#endif
+
+}  // namespace base
+
 using WTF::Vector;
 
 #endif  // WTF_Vector_h
-- 
2.17.0