md5, sha1, sha256, sha512: use openssl routines if available

[gnulib.git] / m4 / gc.m4

diff --git a/m4/gc.m4 b/m4/gc.m4
index 8287d52..3d13354 100644 (file)
--- a/m4/gc.m4
+++ b/m4/gc.m4
@@ -1,15 +1,25 @@
-# gc.m4 serial 8
-dnl Copyright (C) 2005-2006, 2009-2012 Free Software Foundation, Inc.
+# gc.m4 serial 9
+dnl Copyright (C) 2005-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_GC],
 [
+  LIB_CRYPTO=
+  AC_SUBST([LIB_CRYPTO])
   AC_ARG_WITH([libgcrypt],
     AS_HELP_STRING([--with-libgcrypt], [use libgcrypt for low-level crypto]),
     libgcrypt=$withval, libgcrypt=no)
   if test "$libgcrypt" != no; then
-    AC_LIB_HAVE_LINKFLAGS([gcrypt], [gpg-error], [#include <gcrypt.h>])
+    AC_LIB_HAVE_LINKFLAGS([gcrypt], [gpg-error], [
+#include <gcrypt.h>
+/* GCRY_MODULE_ID_USER was added in 1.4.4 and gc-libgcrypt.c
+   will fail on startup if we don't have 1.4.4 or later, so
+   test for it early. */
+#if !defined GCRY_MODULE_ID_USER
+error too old libgcrypt
+#endif
+])
   fi
 ])