m4/rw_prog_cxx_works.m4

   1 # rw_PROG_CXX_WORKS
   2 #
   3 # Check whether the C++ compiler works. There's a bit of oversight in
   4 # autoconf that will set the C++ compiler to g++ if no compiler is found,
   5 # even if g++ is not present! So we need an extra test to make sure that
   6 # the compiler works.
   7 #
   8 AC_DEFUN([rw_PROG_CXX_WORKS], [
   9 AC_REQUIRE([AC_PROG_CXX])
  10 AC_CACHE_CHECK([whether the C++ compiler works],
  11         [rw_cv_prog_cxx_works],
  12         [AC_LANG_PUSH([C++])
  13
  14         AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])], [
  15                 check_cxx_designated_initializers=yes
  16         ], [
  17                 rw_cv_prog_cxx_works=no
  18         ])
  19
  20         AS_IF([test "x$check_cxx_designated_initializers" = "xyes"], [
  21                 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
  22                         struct foo { int a; int b; };
  23                         void fct(void)
  24                         {
  25                                 struct foo f = { .a = 0, .b = 1 };
  26                         }
  27                 ]])], [
  28                         rw_cv_prog_cxx_works=yes
  29                 ], [
  30                         rw_cv_prog_cxx_works=no
  31                 ])
  32         ])
  33
  34         AC_LANG_POP([C++])
  35 ])
  36 ])