[clang] assume_aligned incorrectly diagnoses a dependent return type

Author: AmrDeveloper

clang/include/clang/Sema/Sema.h

@@ -4453,9 +4453,9 @@ class Sema final : public SemaBase {
                                       SourceLocation *ArgLocation = nullptr);
 
   /// Determine if type T is a valid subject for a nonnull and similar
-  /// attributes. By default, we look through references (the behavior used by
-  /// nonnull), but if the second parameter is true, then we treat a reference
-  /// type as valid.
+  /// attributes. By default, we skip dependence and look through references
+  /// (the behavior used by nonnull), but if the second parameter is true, then
+  /// we treat a reference type as valid.
   bool isValidPointerAttrType(QualType T, bool RefOkay = false);
 
   /// AddAssumeAlignedAttr - Adds an assume_aligned attribute to a particular

clang/lib/Sema/SemaDeclAttr.cpp

@@ -1216,6 +1216,8 @@ static void handlePreferredName(Sema &S, Decl *D, const ParsedAttr &AL) {
 }
 
 bool Sema::isValidPointerAttrType(QualType T, bool RefOkay) {
+  if (T->isDependentType())
+    return true;
   if (RefOkay) {
     if (T->isReferenceType())
       return true;
@@ -1284,7 +1286,7 @@ static void handleNonNullAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
     for (unsigned I = 0, E = getFunctionOrMethodNumParams(D);
          I != E && !AnyPointers; ++I) {
       QualType T = getFunctionOrMethodParamType(D, I);
-      if (T->isDependentType() || S.isValidPointerAttrType(T))
+      if (S.isValidPointerAttrType(T))
         AnyPointers = true;
     }
 
@@ -1409,8 +1411,7 @@ void Sema::AddAllocAlignAttr(Decl *D, const AttributeCommonInfo &CI,
   AllocAlignAttr TmpAttr(Context, CI, ParamIdx());
   SourceLocation AttrLoc = CI.getLoc();
 
-  if (!ResultType->isDependentType() &&
-      !isValidPointerAttrType(ResultType, /* RefOkay */ true)) {
+  if (!isValidPointerAttrType(ResultType, /* RefOkay */ true)) {
     Diag(AttrLoc, diag::warn_attribute_return_pointers_refs_only)
         << &TmpAttr << CI.getRange() << getFunctionOrMethodResultSourceRange(D);
     return;

clang/test/SemaCXX/builtin-assume-aligned-tmpl.cpp

@@ -52,6 +52,9 @@ T *atest3() __attribute__((assume_aligned(31, o))); // expected-error {{requeste
 template <typename T, int o>
 T *atest4() __attribute__((assume_aligned(32, o)));
 
+template<typename T>
+T atest5(int) __attribute__((assume_aligned(2)));
+
 void test22() {
   atest3<int, 5>();
   atest4<int, 5>();