[clang] [Clang] Bugfixes and improved support for `AttributedType`s in lambdas (PR #85325)

[Younan Zhang via cfe-commits]

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@@ -13830,61 +13820,27 @@ TreeTransform<Derived>::TransformLambdaExpr(LambdaExpr *E) {
     getSema().AddTemplateParametersToLambdaCallOperator(NewCallOperator, Class,
                                                         TPL);
 
-  // Transform the type of the original lambda's call operator.
-  // The transformation MUST be done in the CurrentInstantiationScope since
-  // it introduces a mapping of the original to the newly created
-  // transformed parameters.
-  TypeSourceInfo *NewCallOpTSI = nullptr;
-  {
-    auto OldCallOpTypeLoc =
-        E->getCallOperator()->getTypeSourceInfo()->getTypeLoc();
-
-    auto TransformFunctionProtoTypeLoc =
-        [this](TypeLocBuilder &TLB, FunctionProtoTypeLoc FPTL) -> QualType {
-      SmallVector<QualType, 4> ExceptionStorage;
-      return this->TransformFunctionProtoType(
-          TLB, FPTL, nullptr, Qualifiers(),
-          [&](FunctionProtoType::ExceptionSpecInfo &ESI, bool &Changed) {
-            return TransformExceptionSpec(FPTL.getBeginLoc(), ESI,
-                                          ExceptionStorage, Changed);
-          });
-    };
-
-    QualType NewCallOpType;
-    TypeLocBuilder NewCallOpTLBuilder;
-
-    if (auto ATL = OldCallOpTypeLoc.getAs<AttributedTypeLoc>()) {
-      NewCallOpType = this->TransformAttributedType(
-          NewCallOpTLBuilder, ATL,
-          [&](TypeLocBuilder &TLB, TypeLoc TL) -> QualType {
-            return TransformFunctionProtoTypeLoc(
-                TLB, TL.castAs<FunctionProtoTypeLoc>());
-          });
----------------
zyn0217 wrote:

Sorry for being dense, but I just wonder why we used to need a different callback for lambda's attribute transformation; wouldn't `TransformType` take us to the same place?

https://github.com/llvm/llvm-project/pull/85325