[clang] f874092 - [Clang][Sema] Check the return value of DiagnoseClassNameShadow in ActOnEnumConstant (#143754)

[via cfe-commits]

Author: Shafik Yaghmour
Date: 2025-08-16T14:08:39-07:00
New Revision: f8740920eec94f04752ad7bf1b86de9587412b1c

URL: https://github.com/llvm/llvm-project/commit/f8740920eec94f04752ad7bf1b86de9587412b1c
DIFF: https://github.com/llvm/llvm-project/commit/f8740920eec94f04752ad7bf1b86de9587412b1c.diff

LOG: [Clang][Sema] Check the return value of DiagnoseClassNameShadow in ActOnEnumConstant (#143754)

Static analysis flagged that we were not checking the return value of
DiagnoseClassNameShadow when we did so everywhere else. Modifying this
case to match how other places uses it makes sense and does not change
behavior. Likely if this check fails later actions will fail as well but
it is more correct to exit early.

Added: 
    

Modified: 
    clang/lib/Sema/SemaDecl.cpp
    clang/test/CXX/class/class.mem/p13.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 5001e080f946b..8ddbaf34a7f47 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -20270,9 +20270,10 @@ Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst,
   // 
diff erent from T:
   // - every enumerator of every member of class T that is an unscoped
   // enumerated type
-  if (getLangOpts().CPlusPlus && !TheEnumDecl->isScoped())
-    DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
-                            DeclarationNameInfo(Id, IdLoc));
+  if (getLangOpts().CPlusPlus && !TheEnumDecl->isScoped() &&
+      DiagnoseClassNameShadow(TheEnumDecl->getDeclContext(),
+                              DeclarationNameInfo(Id, IdLoc)))
+    return nullptr;
 
   EnumConstantDecl *New =
     CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val);

diff  --git a/clang/test/CXX/class/class.mem/p13.cpp b/clang/test/CXX/class/class.mem/p13.cpp
index d947586c41940..a30aa5d0b2ee3 100644
--- a/clang/test/CXX/class/class.mem/p13.cpp
+++ b/clang/test/CXX/class/class.mem/p13.cpp
@@ -114,3 +114,12 @@ template<typename B> struct CtorDtorName : B {
   CtorDtorName();
   ~CtorDtorName(); // expected-error {{identifier 'CtorDtorName' after '~' in destructor name does not name a type}}
 };
+
+struct S { // expected-note {{'S' declared here}}
+  enum E {
+    R = 11,
+    S = 12  // expected-error {{member 'S' has the same name as its class}}
+  };
+  static_assert(E::R == 11, "E::R is not 11");
+  static_assert(E::S == 12, "E::S is not 12");  // expected-error {{no member named 'S' in 'S::E'}}
+};