libqt5-qtwebengine/use-fno-delete-null-pointer-checks-with-gcc-6.diff

From d03c8ccab741952fee6bd54fb56a878c7cc4ca97 Mon Sep 17 00:00:00 2001
From: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>
Date: Fri, 10 Jun 2016 13:26:22 +0200
Subject: [PATCH] Use -fno-delete-null-pointer-checks with gcc 6
MIME-Version: 1.0
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V8 is not safe for removing null pointer checks. Until it is, we need
to disable optimizations in GCC that assume it is not doing something
wrong.

This patch only enables it for v8, and requires it to be activated
by qtwebengine.

Change-Id: I9da15ecf85719f211ba921a620e9d195eff26178
Task-number: QTBUG-53956
Reviewed-by: Michael Brüning <michael.bruning@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
---
 chromium/v8/build/toolchain.gypi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/3rdparty/chromium/v8/build/toolchain.gypi b/src/3rdparty/chromium/v8/build/toolchain.gypi
index 15d6014..2c6fbf6 100644
--- a/src/3rdparty/chromium/v8/build/toolchain.gypi
+++ b/src/3rdparty/chromium/v8/build/toolchain.gypi
@@ -72,6 +72,10 @@
     # Some versions of GCC 4.5 seem to need -fno-strict-aliasing.
     'v8_no_strict_aliasing%': 0,
 
+    # V8 needs support for illegal null this pointers, and must disable
+    # optimizations in GCC 6 that relies on correct behavior.
+    'v8_no_delete_null_pointer_checks%': 0,
+
     # Chrome needs this definition unconditionally. For standalone V8 builds,
     # it's handled in build/standalone.gypi.
     'want_separate_host_toolset%': 1,
@@ -1066,6 +1070,9 @@
           [ 'v8_no_strict_aliasing==1', {
             'cflags': [ '-fno-strict-aliasing' ],
           }],
+          [ 'v8_no_delete_null_pointer_checks==1', {
+            'cflags_cc': [ '-fno-delete-null-pointer-checks' ],
+          }],
         ],  # conditions
       }],
       ['OS=="solaris"', {
-- 
2.7.4