diff --git a/configure.ac b/configure.ac
index 272ea6a..120797e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -165,8 +165,13 @@ AS_IF([test "x$enable_Bsymbolic" = "xcheck"],
 AS_IF([test "x$enable_Bsymbolic" = "xyes"], [JSON_BSYMBOLIC_LDFLAGS=-Wl[,]-Bsymbolic-functions])
 AC_SUBST(JSON_BSYMBOLIC_LDFLAGS)
 
-AX_APPEND_COMPILE_FLAGS([-Wall -Werror -Wcast-qual -Wno-error=deprecated-declarations])
-AX_APPEND_COMPILE_FLAGS([-Wextra -Wwrite-string -Wno-unused-parameter])
+AC_ARG_ENABLE([werror],
+    AS_HELP_STRING([--disable-werror], [avoid treating compiler warnings as fatal errors]))
+
+AS_IF([test "x$enable_werror" != "xno"], [AX_APPEND_COMPILE_FLAGS([-Werror])])
+
+AX_APPEND_COMPILE_FLAGS([-Wall -Wcast-qual -Wno-error=deprecated-declarations])
+AX_APPEND_COMPILE_FLAGS([-Wextra -Wwrite-strings -Wno-unused-parameter])
 AX_APPEND_COMPILE_FLAGS([-D_GNU_SOURCE])
 
 AC_LANG_PUSH([C])
diff --git a/tests/test_deep_copy.c b/tests/test_deep_copy.c
index 7a6e63f..63f882b 100644
--- a/tests/test_deep_copy.c
+++ b/tests/test_deep_copy.c
@@ -186,7 +186,8 @@ int main(int argc, char **argv)
 	printf("\nTesting deep_copy with a custom serializer set\n");
 	json_object *with_serializer = json_object_new_string("notemitted");
 
-	json_object_set_serializer(with_serializer, my_custom_serializer, "dummy userdata", NULL);
+	char udata[] = "dummy userdata";
+	json_object_set_serializer(with_serializer, my_custom_serializer, udata, NULL);
 	json_object_object_add(src1, "with_serializer", with_serializer);
 	dst1 = NULL;
 	/* With a custom serializer in use, a custom shallow_copy function must also be used */
diff --git a/tests/test_double_serializer.c b/tests/test_double_serializer.c
index 21612c8..bb1b8a2 100644
--- a/tests/test_double_serializer.c
+++ b/tests/test_double_serializer.c
@@ -11,16 +11,17 @@
 int main()
 {
 	struct json_object *obj = json_object_new_double(0.5);
+	char udata[] = "test";
 
 	printf("Test default serializer:\n");
 	printf("obj.to_string(standard)=%s\n", json_object_to_json_string(obj));
 
 	printf("Test default serializer with custom userdata:\n");
-	obj->_userdata = "test";
+	obj->_userdata = udata;
 	printf("obj.to_string(userdata)=%s\n", json_object_to_json_string(obj));
 
 	printf("Test explicit serializer with custom userdata:\n");
-	json_object_set_serializer(obj, json_object_double_to_json_string, "test", NULL);
+	json_object_set_serializer(obj, json_object_double_to_json_string, udata, NULL);
 	printf("obj.to_string(custom)=%s\n", json_object_to_json_string(obj));
 
 	printf("Test reset serializer:\n");