From: Alexandre Oliva <oliva@adacore.com>
Date: Fri, 3 Mar 2023 04:46:56 +0000 (-0300)
Subject: [c++] suppress redundant null-addr warn in pfn from pmfn
X-Git-Tag: basepoints/gcc-14~772
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2e8686cb51896e0f89b353ae599c2c1ac5b960d6;p=thirdparty%2Fgcc.git

[c++] suppress redundant null-addr warn in pfn from pmfn

When TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta, when
we warn about comparing a pointer-to-member-function with NULL, we
also warn about comparing the pointer-to-function extracted from it
with NULL, which is redundant.  Suppress the redundant warning.


for  gcc/cp/ChangeLog

	* typeck.cc (cp_build_binary_op): Suppress redundant warning
	for pfn null test in pmfn test with vbit-in-delta.
---

diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc
index 4afb5e4f0d42..d5a3e501d8e9 100644
--- a/gcc/cp/typeck.cc
+++ b/gcc/cp/typeck.cc
@@ -5780,11 +5780,18 @@ cp_build_binary_op (const op_location_t &location,
 
 	      pfn0 = pfn_from_ptrmemfunc (op0);
 	      delta0 = delta_from_ptrmemfunc (op0);
-	      e1 = cp_build_binary_op (location,
-				       EQ_EXPR,
-	  			       pfn0,
-				       build_zero_cst (TREE_TYPE (pfn0)),
-				       complain);
+	      {
+		/* If we will warn below about a null-address compare
+		   involving the orig_op0 ptrmemfunc, we'd likely also
+		   warn about the pfn0's null-address compare, and
+		   that would be redundant, so suppress it.  */
+		warning_sentinel ws (warn_address);
+		e1 = cp_build_binary_op (location,
+					 EQ_EXPR,
+					 pfn0,
+					 build_zero_cst (TREE_TYPE (pfn0)),
+					 complain);
+	      }
 	      e2 = cp_build_binary_op (location,
 				       BIT_AND_EXPR,
 				       delta0,