[clang] Fix mismatched args constructing AddressSpaceAttr.

[AntonBikineev]

Summary

Interestingly enough, but this wasn't caught in tests. I wonder if it's possible to write a test case for it.

[lebedev.ri]

This really needs a test, likely an astdump-one will show it.

[AntonBikineev]

Roman, -ast-dump shows the correct result, because the correct address space is encoded in qualifiers and is passed to Context.getAddrSpaceQualType(...) later in this function. This is why this bug is not observable from the AST. But if you try accessing real Attr* from TypeSourceInfo, you'll see this mismatch.

[AntonBikineev]

Pinging for review..

[AntonBikineev]

Ping.

clang/lib/Sema/SemaType.cpp

if (Attr.getKind() == ParsedAttr::AT_AddressSpace) {
 
     LangAS ASIdx;
     if (!BuildAddressSpaceIndex(S, ASIdx, ASArgExpr, Attr.getLoc())) {
       Attr.setInvalid();
       return;
     }
 
     ASTContext &Ctx = S.Context;
-    auto *ASAttr = ::new (Ctx) AddressSpaceAttr(
-        Attr.getRange(), Ctx, Attr.getAttributeSpellingListIndex(),
-        static_cast<unsigned>(ASIdx));
+    auto *ASAttr = ::new (Ctx)
+        AddressSpaceAttr(Attr.getRange(), Ctx, static_cast<unsigned>(ASIdx),
+                         Attr.getAttributeSpellingListIndex());
 
     // If the expression is not value dependent (not templated), then we can
     // apply the address space qualifiers just to the equivalent type.
     // Otherwise, we make an AttributedType with the modified and equivalent
     // type the same, and wrap it in a DependentAddressSpaceType. When this
     // dependent type is resolved, the qualifier is added to the equivalent type
     // later.
     QualType T;

clang/unittests/AST/ASTTraverserTest.cpp

 { 
 };
 
 template<>
 struct templ<int>
 { 
 };
 
+void parmvardecl_attr(struct A __attribute__((address_space(19)))*);
+
 )cpp");
 
   const FunctionDecl *Func = getFunctionNode(AST.get(), "func");
 
   verifyWithDynNode(Func,
                     R"cpp(
 CXXMethodDecl
 |-CompoundStmt
)cpp";
   auto Templ = Result[0].getNodeAs<ClassTemplateSpecializationDecl>("fn");
 
   TemplateArgument TA = Templ->getTemplateArgs()[0];
 
   verifyWithDynNode(TA,
                     R"cpp(
 TemplateArgument
 )cpp");
+
+  Func = getFunctionNode(AST.get(), "parmvardecl_attr");
+
+  const auto *Parm = Func->getParamDecl(0);
+  const auto TL = Parm->getTypeSourceInfo()->getTypeLoc();
+  ASSERT_TRUE(TL.getType()->isPointerType());
+
+  const auto ATL = TL.getNextTypeLoc().getAs<AttributedTypeLoc>();
+  const auto *AS = cast<AddressSpaceAttr>(ATL.getAttr());
+  EXPECT_EQ(toTargetAddressSpace(static_cast<LangAS>(AS->getAddressSpace())),
+            19u);
 }
 } // namespace clang