--- a/configure.ac
+++ b/configure.ac
@@ -454,16 +454,6 @@ if test $ondarwin -eq 1; then
 else
     stdc="gnu"
 fi
-AC_RUN_IFELSE(
-[AC_LANG_PROGRAM([], [dnl
-        #ifdef __STDC_VERSION__
-        #if __STDC_VERSION__ >= 201112L
-        return 0;
-        #endif
-        #endif
-        return 1;
-        ])], [CFLAGS="$CFLAGS -std=${stdc}11"], [CFLAGS="$CFLAGS -std=${stdc}99"])
-AC_CHECK_HEADERS([stdint.h stdbool.h], [], [AC_MSG_ERROR([toolchain does not have C99 headers])])
 
 # ---------------------------------------------------------------------------
 # Outputs