From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 1 May 2025 17:06:45 +0000 (+0200)
Subject: c: Suppress -Wdeprecated-non-prototype warnings for builtins
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b6d37ec1dd2a228d94e7b5b438f3aa53684316bc;p=thirdparty%2Fgcc.git

c: Suppress -Wdeprecated-non-prototype warnings for builtins

Builtins defined with BT_FN_INT_VAR etc. show as functions without
a prototype and trigger the warning.

gcc/c/

	PR c/119950
	* c-typeck.cc (convert_arguments): Check for built-in
	function declaration before warning.

gcc/testsuite/

	* gcc.dg/Wdeprecated-non-prototype-5.c: New test.
---

diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index d94ecb5b743..c7a13bf2b2f 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -4336,7 +4336,8 @@ convert_arguments (location_t loc, vec<location_t> arg_loc, tree fntype,
 	  builtin_typetail = NULL_TREE;
 	}
 
-      if (!typetail && parmnum == 0 && !TYPE_NO_NAMED_ARGS_STDARG_P (fntype))
+      if (!typetail && parmnum == 0 && !TYPE_NO_NAMED_ARGS_STDARG_P (fntype)
+	  && !fndecl_built_in_p (fundecl))
 	{
 	  auto_diagnostic_group d;
 	  bool warned;
diff --git a/gcc/testsuite/gcc.dg/Wdeprecated-non-prototype-5.c b/gcc/testsuite/gcc.dg/Wdeprecated-non-prototype-5.c
new file mode 100644
index 00000000000..b231a74cebe
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/Wdeprecated-non-prototype-5.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-Wdeprecated-non-prototype" } */
+
+static inline
+int f (int x)
+{
+  return __builtin_constant_p (x);
+}
+
+static inline
+int g (double x)
+{
+  return __builtin_isfinite (x);
+}