buildroot/package/qt5/qt5base/0001-Disable-c-standard-compiler-flags-for-the-host-build.patch

From e69e69519661954716d59bfa5bbd0626515cfda9 Mon Sep 17 00:00:00 2001
From: Peter Seiderer <ps.report@gmx.net>
Date: Thu, 3 Mar 2016 15:17:31 +0100
Subject: [PATCH] Disable c++ standard compiler flags for the host build
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There is no test for c++ standard support for the host build
(only for the target compiler/build) which leads to trouble
in some cross compiling environments (old host compiler, new
cross compiler):

  g++: error: unrecognized command line option ‘-std=c++1z’

So disable c++ standard compiler flags unconditionally for host builds.

Task-number: QTBUG-51644
Change-Id: Ifb3042e125fe199a7e081740d1171d26ccacf0c5
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
---
 mkspecs/features/default_post.prf | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/mkspecs/features/default_post.prf b/mkspecs/features/default_post.prf
index cd8d885..561c8f4 100644
--- a/mkspecs/features/default_post.prf
+++ b/mkspecs/features/default_post.prf
@@ -95,7 +95,10 @@ breakpad {
     !isEmpty(QMAKE_STRIP):QMAKE_POST_LINK = $$QMAKE_POST_LINK$$escape_expand(\\n\\t)$$quote($$QMAKE_STRIP $$DEBUGFILENAME)
 }
 
-c++11|c++14|c++1z {
+# Disable special compiler flags for host builds (needs to be changed for 5.7
+# to fall back to c++11 because since 5.7 c++11 is required everywhere,
+# including host builds).
+if(!host_build|!cross_compile):if(c++11|c++14|c++1z) {
     c++1z:       cxxstd = CXX1Z
     else: c++14: cxxstd = CXX14
     else:        cxxstd = CXX11
-- 
2.1.4