folly: Check if __cpp_concepts is defined before checking its value

Summary: This diff updates a check against __cpp_concepts to first make sure it is defined. Reviewed By: Gownta Differential Revision: D67203697 fbshipit-source-id: ae5bd07a5f7945645503cc1ac15bdc5b602b61c0
facebook · Dec 14, 2024 · 3395281 · 3395281
1 parent 889f0ad
commit 3395281
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/folly/container/detail/F14Table.h b/folly/container/detail/F14Table.h
@@ -250,7 +250,7 @@ class F14HashToken final {
 };
 #endif
 
-#if __cpp_concepts && __has_include(<concepts>)
+#if defined(__cpp_concepts) && __cpp_concepts && __has_include(<concepts>)
 static_assert(std::regular<F14HashToken>);
 #endif