[Sema] Avoid emitting warnings for constant destruction.

Fixes #62436. Reviewed By: rsmith Differential Revision: https://reviews.llvm.org/D149713
llvm · May 6, 2023 · dd6a58b · dd6a58b
1 parent e8e8707
commit dd6a58b
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Showing 3 changed files with 44 additions and 3 deletions.
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -15732,7 +15732,8 @@ void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
     }
   }
 
-  if (!VD->hasGlobalStorage()) return;
+  if (!VD->hasGlobalStorage() || !VD->needsDestruction(Context))
+    return;
 
   // Emit warning for non-trivial dtor in global scope (a real global,
   // class-static, function-static).

diff --git a/clang/test/SemaCXX/warn-exit-time-destructors.cpp b/clang/test/SemaCXX/warn-exit-time-destructors.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -std=c++11 -fsyntax-only -Wexit-time-destructors %s -verify
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only -Wexit-time-destructors %s -verify=expected,cxx11
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -Wexit-time-destructors %s -verify=expected
 
 namespace test1 {
   struct A { ~A(); };
@@ -48,3 +49,22 @@ namespace test4 {
 struct A { ~A(); };
 [[clang::no_destroy]] A a; // no warning
 }
+
+namespace test5 {
+#if __cplusplus >= 202002L
+#define CPP20_CONSTEXPR constexpr
+#else
+#define CPP20_CONSTEXPR
+#endif
+  struct S {
+    CPP20_CONSTEXPR ~S() {}
+  };
+  S s; // cxx11-warning {{exit-time destructor}}
+
+  struct T {
+    CPP20_CONSTEXPR ~T() { if (b) {} }
+    bool b;
+  };
+  T t; // expected-warning {{exit-time destructor}}
+#undef CPP20_CONSTEXPR
+}
diff --git a/clang/test/SemaCXX/warn-global-constructors.cpp b/clang/test/SemaCXX/warn-global-constructors.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -std=c++11 -fsyntax-only -Wglobal-constructors %s -verify
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only -Wglobal-constructors %s -verify=expected,cxx11
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -Wglobal-constructors %s -verify=expected
 
 int opaque_int();
 
@@ -145,3 +146,22 @@ namespace bitfields {
   const HasUnnamedBitfield nonConstexprConst{1}; // expected-warning {{global constructor}}
   HasUnnamedBitfield nonConstexprMutable{1}; // expected-warning {{global constructor}}
 }
+
+namespace test7 {
+#if __cplusplus >= 202002L
+#define CPP20_CONSTEXPR constexpr
+#else
+#define CPP20_CONSTEXPR
+#endif
+  struct S {
+    CPP20_CONSTEXPR ~S() {}
+  };
+  S s; // cxx11-warning {{global destructor}}
+
+  struct T {
+    CPP20_CONSTEXPR ~T() { if (b) {} }
+    bool b;
+  };
+  T t; // expected-warning {{global destructor}}
+#undef CPP20_CONSTEXPR
+}