dnl Available from the GNU Autoconf Macro Archive at:
dnl http://www.gnu.org/software/ac-archive/htmldoc/ax_lang_compiler_ms.html
dnl
AC_DEFUN([AX_LANG_COMPILER_MS],
[AC_CACHE_CHECK([whether we are using the Microsoft _AC_LANG compiler],
                [ax_cv_[]_AC_LANG_ABBREV[]_compiler_ms],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[#ifndef _MSC_VER
       choke me
#endif
]])],
                   [ax_compiler_ms=yes],
                   [ax_compiler_ms=no])
ax_cv_[]_AC_LANG_ABBREV[]_compiler_ms=$ax_compiler_ms
])])