[HIP][OpenMP] Fix assertion in deferred diag due to incomplete class definition

[yaxunl]

Summary

Fix assertion in UsedDeclVisitor where clang is trying to look up a destructor for
a forward declared class.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=52250

[tra]

Looks reasonable to me, but, considering that it's generic C++ code, I think it would be prudent go double check that.

@rsmith - WDYT?

[rjmccall]

Minor grammar nit with a comment, but otherwise LGTM.

clang/test/OpenMP/deferred-diags.cpp

40

"Test that deleting an incomplete class type doesn't cause an assertion."

[yaxunl]

clang/test/OpenMP/deferred-diags.cpp

40

will do when committing

clang/lib/Sema/UsedDeclVisitor.h

public:
   void VisitCXXDeleteExpr(CXXDeleteExpr *E) {
     if (E->getOperatorDelete())
       asImpl().visitUsedDecl(E->getBeginLoc(), E->getOperatorDelete());
     QualType DestroyedOrNull = E->getDestroyedType();
     if (!DestroyedOrNull.isNull()) {
       QualType Destroyed = S.Context.getBaseElementType(DestroyedOrNull);
       if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) {
         CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl());
+        if (Record->getDefinition())
           asImpl().visitUsedDecl(E->getBeginLoc(), S.LookupDestructor(Record));
       }
     }
 
     Inherited::VisitCXXDeleteExpr(E);
   }
 
   void VisitCXXConstructExpr(CXXConstructExpr *E) {
     asImpl().visitUsedDecl(E->getBeginLoc(), E->getConstructor());

clang/test/OpenMP/deferred-diags.cpp

 // RUN: %clang_cc1 -triple x86_64 -verify=expected,dev -std=c++11\
 // RUN:            -verify-ignore-unexpected=note \
 // RUN:            -fopenmp -fopenmp-version=45 -o - %s
 
 // RUN: %clang_cc1 -triple x86_64 -verify=expected,dev -std=c++11\
 // RUN:            -verify-ignore-unexpected=note \
 // RUN:            -fopenmp -o - %s
 
-// expected-no-diagnostics
-
 // Test no infinite recursion in DeferredDiagnosticEmitter.
 constexpr int foo(int *x) {
   return 0;
 }
 
 int a = foo(&a);
 
 // Test no crash when both caller and callee have target directives.

 public:
   void barA(int *isHost) {
   #pragma omp target map(tofrom: isHost)
      {
        barB(isHost);
      }
   }
 };
+
+// Test that deleting an incomplete class type doesn't cause an assertion.
+namespace TestDeleteIncompleteClassDefinition {
+struct a;
+struct b {
+  b() {
+    delete c; // expected-warning {{deleting pointer to incomplete type 'TestDeleteIncompleteClassDefinition::a' may cause undefined behavior}}
+  }
+  a *c;
+};
+} // namespace TestDeleteIncompleteClassDefinition