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   1 # ===========================================================================
   2 #        http://autoconf-archive.cryp.to/ac_cxx_compile_stdcxx_0x.html
   3 # ===========================================================================
   4 #
   5 # SYNOPSIS
   6 #
   7 #   AC_CXX_COMPILE_STDCXX_0X
   8 #
   9 # DESCRIPTION
  10 #
  11 #   Check for baseline language coverage in the compiler for the C++0x
  12 #   standard.
  13 #
  14 # LICENSE
  15 #
  16 #   Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com>
  17 #
  18 #   Copying and distribution of this file, with or without modification, are
  19 #   permitted in any medium without royalty provided the copyright notice
  20 #   and this notice are preserved.
  21
  22 AC_DEFUN([AC_CXX_COMPILE_STDCXX_0X], [
  23   AC_CACHE_CHECK(if g++ supports C++0x features without additional flags,
  24   ac_cv_cxx_compile_cxx0x_native,
  25   [AC_LANG_SAVE
  26   AC_LANG_CPLUSPLUS
  27   AC_TRY_COMPILE([
  28   template <typename T>
  29     struct check
  30     {
  31       static_assert(sizeof(int) <= sizeof(T), "not big enough");
  32     };
  33
  34     typedef check<check<bool>> right_angle_brackets;
  35
  36     int a;
  37     decltype(a) b;
  38
  39     typedef check<int> check_type;
  40     check_type c;
  41     check_type&& cr = c;],,
  42   ac_cv_cxx_compile_cxx0x_native=yes, ac_cv_cxx_compile_cxx0x_native=no)
  43   AC_LANG_RESTORE
  44   ])
  45
  46   AC_CACHE_CHECK(if g++ supports C++0x features with -std=c++0x,
  47   ac_cv_cxx_compile_cxx0x_cxx,
  48   [AC_LANG_SAVE
  49   AC_LANG_CPLUSPLUS
  50   ac_save_CXXFLAGS="$CXXFLAGS"
  51   CXXFLAGS="$CXXFLAGS -std=c++0x"
  52   AC_TRY_COMPILE([
  53   template <typename T>
  54     struct check
  55     {
  56       static_assert(sizeof(int) <= sizeof(T), "not big enough");
  57     };
  58
  59     typedef check<check<bool>> right_angle_brackets;
  60
  61     int a;
  62     decltype(a) b;
  63
  64     typedef check<int> check_type;
  65     check_type c;
  66     check_type&& cr = c;],,
  67   ac_cv_cxx_compile_cxx0x_cxx=yes, ac_cv_cxx_compile_cxx0x_cxx=no)
  68   CXXFLAGS="$ac_save_CXXFLAGS"
  69   AC_LANG_RESTORE
  70   ])
  71
  72   AC_CACHE_CHECK(if g++ supports C++0x features with -std=gnu++0x,
  73   ac_cv_cxx_compile_cxx0x_gxx,
  74   [AC_LANG_SAVE
  75   AC_LANG_CPLUSPLUS
  76   ac_save_CXXFLAGS="$CXXFLAGS"
  77   CXXFLAGS="$CXXFLAGS -std=gnu++0x"
  78   AC_TRY_COMPILE([
  79   template <typename T>
  80     struct check
  81     {
  82       static_assert(sizeof(int) <= sizeof(T), "not big enough");
  83     };
  84
  85     typedef check<check<bool>> right_angle_brackets;
  86
  87     int a;
  88     decltype(a) b;
  89
  90     typedef check<int> check_type;
  91     check_type c;
  92     check_type&& cr = c;],,
  93   ac_cv_cxx_compile_cxx0x_gxx=yes, ac_cv_cxx_compile_cxx0x_gxx=no)
  94   CXXFLAGS="$ac_save_CXXFLAGS"
  95   AC_LANG_RESTORE
  96   ])
  97
  98   if test "$ac_cv_cxx_compile_cxx0x_native" = yes ||
  99      test "$ac_cv_cxx_compile_cxx0x_cxx" = yes ||
 100      test "$ac_cv_cxx_compile_cxx0x_gxx" = yes; then
 101     AC_DEFINE(HAVE_STDCXX_0X,,[Define if g++ supports C++0x features. ])
 102   fi
 103 ])