Hi Volodymyr, This broke the Chrome build in an interesting way. Here's a reduced repro:
$ cat /tmp/a.mm #import <AVFoundation/AVFoundation.h> void f(int width, int height) { FourCharCode best_fourcc = kCMPixelFormat_422YpCbCr8_yuvs; NSDictionary* videoSettingsDictionary = @{ (id)kCVPixelBufferPixelFormatTypeKey : @(best_fourcc), }; } $ build.release/bin/clang++ -isysroot /work/chromium/src/build/mac_files/xcode_binaries/Contents/Developer/Platforms/MacOSX.platform/Developer/SDK s/MacOSX10.14.sdk -c /tmp/a.mm /tmp/a.mm:6:5: error: cannot initialize a parameter of type 'KeyType<NSCopying> _Nonnull const' (aka 'const id') with an rvalue of type 'id' (id)kCVPixelBufferPixelFormatTypeKey : @(best_fourcc), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated. To me, the "cannot initialize a parameter of type [nanana] (aka 'const id') with an rvalue of type 'id'" message looks strange, but I'm not an Obj-C expert. Is this expected behaviour, and if so how should we change our code? Thanks, Hans On Wed, Oct 9, 2019 at 12:26 PM Volodymyr Sapsai via cfe-commits <cfe-commits@lists.llvm.org> wrote: > > Author: vsapsai > Date: Wed Oct 9 12:29:13 2019 > New Revision: 374202 > > URL: http://llvm.org/viewvc/llvm-project?rev=374202&view=rev > Log: > [ObjC generics] Fix not inheriting type bounds in categories/extensions. > > When a category/extension doesn't repeat a type bound, corresponding > type parameter is substituted with `id` when used as a type argument. As > a result, in the added test case it was causing errors like > > > type argument 'T' (aka 'id') does not satisfy the bound ('id<NSCopying>') > > of type parameter 'T' > > We are already checking that type parameters should be consistent > everywhere (see `checkTypeParamListConsistency`) and update > `ObjCTypeParamDecl` to have correct underlying type. And when we use the > type parameter as a method return type or a method parameter type, it is > substituted to the bounded type. But when we use the type parameter as a > type argument, we check `ObjCTypeParamType` that ignores the updated > underlying type and remains `id`. > > Fix by desugaring `ObjCTypeParamType` to the underlying type, the same > way we are doing with `TypedefType`. > > rdar://problem/54329242 > > Reviewers: erik.pilkington, ahatanak > > Reviewed By: erik.pilkington > > Subscribers: jkorous, dexonsmith, ributzka, cfe-commits > > Differential Revision: https://reviews.llvm.org/D66696 > > Modified: > cfe/trunk/include/clang/AST/Type.h > cfe/trunk/lib/AST/Type.cpp > cfe/trunk/test/SemaObjC/parameterized_classes_subst.m > > Modified: cfe/trunk/include/clang/AST/Type.h > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Type.h?rev=374202&r1=374201&r2=374202&view=diff > ============================================================================== > --- cfe/trunk/include/clang/AST/Type.h (original) > +++ cfe/trunk/include/clang/AST/Type.h Wed Oct 9 12:29:13 2019 > @@ -5569,7 +5569,7 @@ class ObjCTypeParamType : public Type, > > public: > bool isSugared() const { return true; } > - QualType desugar() const { return getCanonicalTypeInternal(); } > + QualType desugar() const; > > static bool classof(const Type *T) { > return T->getTypeClass() == ObjCTypeParam; > > Modified: cfe/trunk/lib/AST/Type.cpp > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Type.cpp?rev=374202&r1=374201&r2=374202&view=diff > ============================================================================== > --- cfe/trunk/lib/AST/Type.cpp (original) > +++ cfe/trunk/lib/AST/Type.cpp Wed Oct 9 12:29:13 2019 > @@ -663,6 +663,10 @@ ObjCTypeParamType::ObjCTypeParamType(con > initialize(protocols); > } > > +QualType ObjCTypeParamType::desugar() const { > + return getDecl()->getUnderlyingType(); > +} > + > ObjCObjectType::ObjCObjectType(QualType Canonical, QualType Base, > ArrayRef<QualType> typeArgs, > ArrayRef<ObjCProtocolDecl *> protocols, > > Modified: cfe/trunk/test/SemaObjC/parameterized_classes_subst.m > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/parameterized_classes_subst.m?rev=374202&r1=374201&r2=374202&view=diff > ============================================================================== > --- cfe/trunk/test/SemaObjC/parameterized_classes_subst.m (original) > +++ cfe/trunk/test/SemaObjC/parameterized_classes_subst.m Wed Oct 9 12:29:13 > 2019 > @@ -467,3 +467,17 @@ void bar(MyMutableDictionary<NSString *, > - (void)mapUsingBlock2:(id)block { // expected-warning{{conflicting > parameter types in implementation}} > } > @end > + > +// -------------------------------------------------------------------------- > +// Use a type parameter as a type argument. > +// -------------------------------------------------------------------------- > +// Type bounds in a category/extension are omitted. rdar://problem/54329242 > +@interface ParameterizedContainer<T : id<NSCopying>> > +- (ParameterizedContainer<T> *)inInterface; > +@end > +@interface ParameterizedContainer<T> (Cat) > +- (ParameterizedContainer<T> *)inCategory; > +@end > +@interface ParameterizedContainer<U> () > +- (ParameterizedContainer<U> *)inExtension; > +@end > > > _______________________________________________ > cfe-commits mailing list > cfe-commits@lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits