Allow ODR for ObjC/C in the sense that we won't keep more that
one definition around (merge them). However, ensure the decl
pass the structural compatibility check in C11 6.2.7/1, for that,
reuse the structural equivalence checks used by the ASTImporter.
Few other considerations:
- Create error diagnostics for tag types mismatches and thread
them into the structural equivalence checks.
- Note that by doing this we only support redefinition between types
that are considered "compatible types" by C.
This is mixed approach of the suggestions discussed in
http://lists.llvm.org/pipermail/cfe-dev/2017-March/053257.html
Differential Revision: https://reviews.llvm.org/D31778
rdar://problem/31909368
llvm-svn: 306918
ASTImporter has some bugs when it's importing types
that themselves come from an ExternalASTSource. This
is exposed particularly in the behavior when
comparing complete TagDecls with forward
declarations. This patch does several things:
- Adds a test case making sure that conflicting
forward-declarations are resolved correctly;
- Extends the clang-import-test harness to test
two-level importing, so that we make sure we
complete types when necessary; and
- Fixes a few bugs I found this way. Failure to
complete types was one; however, I also discovered
that complete RecordDecls aren't properly added to
the redecls chain for existing forward
declarations.
llvm-svn: 302975
Create a header and impl file for the structural equivalence context.
This is to allow other users outside clang importer. NFCI
Differential Revision: https://reviews.llvm.org/D31777
rdar://problem/30167717
llvm-svn: 301604