[clang] 8bd7fc7 - [ExprMutation] fix false postives on pointer-to-member operator (#166069)

[via cfe-commits]

Author: Congcong Cai
Date: 2025-11-03T13:36:10Z
New Revision: 8bd7fc7211782e7b2ba76070ee6af46f4913a185

URL: https://github.com/llvm/llvm-project/commit/8bd7fc7211782e7b2ba76070ee6af46f4913a185
DIFF: https://github.com/llvm/llvm-project/commit/8bd7fc7211782e7b2ba76070ee6af46f4913a185.diff

LOG: [ExprMutation] fix false postives on pointer-to-member operator (#166069)

Fixed: #161913

---------

Co-authored-by: Baranov Victor <bar.victor.2002 at gmail.com>

Added: 
    

Modified: 
    clang-tools-extra/docs/ReleaseNotes.rst
    clang/lib/Analysis/ExprMutationAnalyzer.cpp
    clang/unittests/Analysis/ExprMutationAnalyzerTest.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 35a64395f04e9..26f00e9a8a294 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -379,7 +379,8 @@ Changes in existing checks
   <clang-tidy/checks/misc/const-correctness>` check to avoid false
   positives when pointers is transferred to non-const references
   and avoid false positives of function pointer and fix false
-  positives on return of non-const pointer.
+  positives on return of non-const pointer and fix false positives on
+  pointer-to-member operator.
 
 - Improved :doc:`misc-header-include-cycle
   <clang-tidy/checks/misc/header-include-cycle>` check performance.

diff  --git a/clang/lib/Analysis/ExprMutationAnalyzer.cpp b/clang/lib/Analysis/ExprMutationAnalyzer.cpp
index 75b17c545bb78..54c30c05c3e19 100644
--- a/clang/lib/Analysis/ExprMutationAnalyzer.cpp
+++ b/clang/lib/Analysis/ExprMutationAnalyzer.cpp
@@ -746,11 +746,14 @@ ExprMutationAnalyzer::Analyzer::findPointeeMemberMutation(const Expr *Exp) {
                     Stm, Context));
   if (MemberCallExpr)
     return MemberCallExpr;
-  const auto Matches =
-      match(stmt(forEachDescendant(
-                memberExpr(hasObjectExpression(canResolveToExprPointee(Exp)))
-                    .bind(NodeID<Expr>::value))),
-            Stm, Context);
+  const auto Matches = match(
+      stmt(forEachDescendant(
+          expr(anyOf(memberExpr(
+                         hasObjectExpression(canResolveToExprPointee(Exp))),
+                     binaryOperator(hasOperatorName("->*"),
+                                    hasLHS(canResolveToExprPointee(Exp)))))
+              .bind(NodeID<Expr>::value))),
+      Stm, Context);
   return findExprMutation(Matches);
 }
 

diff  --git a/clang/unittests/Analysis/ExprMutationAnalyzerTest.cpp b/clang/unittests/Analysis/ExprMutationAnalyzerTest.cpp
index ef229606de0f0..8fc9a66dbda7e 100644
--- a/clang/unittests/Analysis/ExprMutationAnalyzerTest.cpp
+++ b/clang/unittests/Analysis/ExprMutationAnalyzerTest.cpp
@@ -2076,4 +2076,19 @@ TEST(ExprMutationAnalyzerTest, PointeeMutatedByReturn) {
   }
 }
 
+TEST(ExprMutationAnalyzerTest, PointeeMutatedByPointerToMemberOperator) {
+  // GH161913
+  const std::string Code = R"(
+    struct S { int i; };
+    void f(S s) {
+      S *x = &s;
+      (x->*(&S::i))++;
+    }
+  )";
+  auto AST = buildASTFromCodeWithArgs(Code, {"-Wno-everything"});
+  auto Results =
+      match(withEnclosingCompound(declRefTo("x")), AST->getASTContext());
+  EXPECT_TRUE(isPointeeMutated(Results, AST.get()));
+}
+
 } // namespace clang