m4/rw_prog_cxx_works.m4

   1 # SYNOPSIS
   2 #
   3 #   RW_PROG_CXX_WORKS
   4 #
   5 # DESCRIPTION
   6 #
   7 #   RW_PROG_CXX_WORKS checks whether the C++ compiler works.
   8 #
   9 #   There's a bit of oversight in autoconf that will set the C++ compiler to
  10 #   g++ if no compiler is found, even if g++ is not present! So we need an
  11 #   extra test to make sure that the compiler works.
  12 #
  13 # LICENSE
  14 #
  15 #   Copying and distribution of this file, with or without modification, are
  16 #   permitted in any medium without royalty provided the copyright notice
  17 #   and this notice are preserved. This file is offered as-is, without any
  18 #   warranty.
  19
  20 #serial 1
  21
  22 AC_DEFUN([RW_PROG_CXX_WORKS], [
  23 AC_REQUIRE([AC_PROG_CXX])
  24 AC_CACHE_CHECK([whether the C++ compiler works],
  25         [rw_cv_prog_cxx_works],
  26         [AC_LANG_PUSH([C++])
  27
  28         AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])], [
  29                 check_cxx_designated_initializers=yes
  30         ], [
  31                 rw_cv_prog_cxx_works=no
  32         ])
  33
  34         AS_IF([test "x$check_cxx_designated_initializers" = "xyes"], [
  35                 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
  36                         struct foo { int a; int b; };
  37                         void fct(void)
  38                         {
  39                                 struct foo f = { .a = 0, .b = 1 };
  40                         }
  41                 ]])], [
  42                         rw_cv_prog_cxx_works=yes
  43                 ], [
  44                         rw_cv_prog_cxx_works=no
  45                 ])
  46         ])
  47
  48         AC_LANG_POP([C++])
  49 ])
  50 ])