Improve detection of C++11 mode

This replaces commit 329eae56 with a better solution. Indeed, while
__cpluplus is useless with g++ 4.[3-6] because its value is always 1,
these compilers define __GXX_EXPERIMENTAL_CXX0X__ when "-std c++0x" is used.

Therefore the code now relies on both macros to detect C++11 mode
instead of setting it when --enable-cxx11 is used.

Also, use pure c++ mode instead of gnu++ extensions on gcc
This commit is contained in:
Jean-Marc Lasgouttes 2015-09-03 10:22:56 +02:00
parent 0e62745995
commit 67385e69fc
2 changed files with 10 additions and 5 deletions

View File

@ -160,11 +160,10 @@ AC_DEFUN([LYX_LIB_STDCXX],
dnl Usage: LYX_CXX_USE_CXX11(STD): pass option -std=STD to the C++ compiler
dnl and define LYX_USE_CXX11.
dnl and update lyxflags
AC_DEFUN([LYX_CXX_USE_CXX11],
[lyx_flags="$lyx_flags c++11-mode"
[lyx_flags="$lyx_flags c++11"
AM_CXXFLAGS="$AM_CXXFLAGS -std=$1"
AC_DEFINE([LYX_USE_CXX11], 1, [Define if LyX should use C++11 features])
])
@ -338,13 +337,15 @@ if test x$GXX = xyes; then
case $gxx_version in
4.0*|4.1*|4.2*) AC_ERROR([There is no C++11 support in gcc 4.2 or older]);;
4.3*|4.4*|4.5*|4.6*)
LYX_CXX_USE_CXX11(gnu++0x);;
dnl Note that this will define __GXX_EXPERIMENTAL_CXX0X__.
dnl The source code relies on that.
LYX_CXX_USE_CXX11(c++0x);;
clang)
dnl presumably all clang version support c++11.
dnl the deprecated-register warning is very annoying with Qt4.x right now.
LYX_CXX_USE_CXX11(c++11 -Wno-deprecated-register);;
*)
LYX_CXX_USE_CXX11(gnu++11);;
LYX_CXX_USE_CXX11(c++11);;
esac
if test x$CLANG = xno || test $lyx_cv_lib_stdcxx = yes; then
dnl <regex> in gcc is unusable in versions less than 4.9.0

View File

@ -276,6 +276,10 @@ AH_BOTTOM([
/************************************************************
** You should not need to change anything beyond this point */
#if __cplusplus >= 201103L || defined(__GXX_EXPERIMENTAL_CXX0X__)
#define LYX_USE_CXX11
#endif
#ifndef HAVE_STRERROR
#if defined(__cplusplus)
extern "C"