diff --git a/src/webp/types.h b/src/webp/types.h
index 9c17edec..a0363f1c 100644
--- a/src/webp/types.h
+++ b/src/webp/types.h
@@ -38,11 +38,11 @@ typedef long long int int64_t;
 
 #ifndef WEBP_NODISCARD
 #if defined(WEBP_ENABLE_NODISCARD) && WEBP_ENABLE_NODISCARD
-#if (defined(__cplusplus) && __cplusplus >= 201700L) || \
+#if (defined(__cplusplus) && __cplusplus >= 201703L) || \
     (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L)
 #define WEBP_NODISCARD [[nodiscard]]
 #else
-// gcc's __has_attribute does not work for enums.
+// gcc's __attribute__((warn_unused_result)) does not work for enums.
 #if defined(__clang__) && defined(__has_attribute)
 #if __has_attribute(warn_unused_result)
 #define WEBP_NODISCARD __attribute__((warn_unused_result))