[Clang] fix assertion failure in invalid delete operator declaration check (#99308)

Fixes #96191

Author: a-tarasyuk

clang/docs/ReleaseNotes.rst

@@ -150,6 +150,7 @@ Bug Fixes to C++ Support
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
 - Fixed a crash when an expression with a dependent ``__typeof__`` type is used as the operand of a unary operator. (#GH97646)
+- Fixed a failed assertion when checking invalid delete operator declaration. (#GH96191)
 
 Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^

clang/lib/Sema/SemaExprCXX.cpp

@@ -3806,6 +3806,9 @@ Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
                                                      Overaligned, DeleteName);
     }
 
+    if (OperatorDelete->isInvalidDecl())
+      return ExprError();
+
     MarkFunctionReferenced(StartLoc, OperatorDelete);
 
     // Check access and ambiguity of destructor if we're going to call it.

clang/test/SemaCXX/cxx2a-destroying-delete.cpp

@@ -187,3 +187,12 @@ namespace delete_from_new {
 #endif
   }
 }
+
+namespace GH96191 {
+  struct S {};
+  struct T {
+    void operator delete(S) { } // expected-error {{first parameter of 'operator delete' must have type 'void *'}}
+  };
+
+  void foo(T *t) { delete t; }
+}