diff --git a/configure.ac b/configure.ac
index 72a134d..2c07a30 100644
--- a/configure.ac
+++ b/configure.ac
@@ -65,7 +65,18 @@
 
 # Checks for programs.
 AC_PROG_CC
-AX_CHECK_COMPILE_FLAG([-std=c11], [CFLAGS+=" -std=c11"], [AC_PROG_CC_C99])
+AC_ARG_ENABLE([c11],
+    [AS_HELP_STRING([--enable-c11],
+        [enable C11 for C compiler [default=no]])],
+    [zmq_enable_c11=$enableval],
+    [zmq_enable_c11="no"])
+if test "x$zmq_enable_c11" != "xno"; then
+    AX_CHECK_COMPILE_FLAG([-std=gnu11],
+        [CFLAGS+=" -std=gnu11"],
+        [AC_MSG_ERROR([C11 requested but not supported by the compiler.])])
+else
+    AC_PROG_CC_C99
+fi
 AC_PROG_CXX
 AX_CODE_COVERAGE
 AM_PROG_CC_C_O