configure: fix warnings

Finally!

Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/configure.ac b/configure.ac
index 5e9f70fcb5969e59ce81f4d7def8132a8686d491..30cd7b951120e4f04e6c4e528aa7e189997d0cba 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -58,7 +58,7 @@ AC_DEFUN([AC_CHECK_CC_FLAG],
        my_cflags_save="$CFLAGS"
        CFLAGS="$my_cflags_save $1"
        AC_MSG_CHECKING([whether $CC accepts $1])
-       AC_COMPILE_IFELSE(AC_LANG_PROGRAM(),
+       AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[ ]], [[ ]])],
                          [AC_MSG_RESULT([yes]); AC_SUBST([$2], ["$1"])],
                          [AC_MSG_RESULT([no])]
                         )