Summary:
We fail to import a `ClassTemplateDecl` if the "To" context already
contains a definition and then a forward decl. This is because
`localUncachedLookup` does not find the definition. This is not a
lookup error, the parser behaves differently than assumed in the
importer code. A `DeclContext` contains one DenseMap (`LookupPtr`)
which maps names to lists. The list is a special list `StoredDeclsList`
which is optimized to have one element. During building the initial
AST, the parser first adds the definition to the `DeclContext`. Then
during parsing the second declaration (the forward decl) the parser
again calls `DeclContext::addDecl` but that will not add a new element
to the `StoredDeclsList` rarther it simply overwrites the old element
with the most recent one. This patch fixes the error by finding the
definition in the redecl chain. Added tests for the same issue with
`CXXRecordDecl` and with `ClassTemplateSpecializationDecl`. These tests
pass and they pass because in `VisitRecordDecl` and in
`VisitClassTemplateSpecializationDecl` we already use
`D->getDefinition()` after the lookup.
Reviewers: a.sidorin, xazax.hun, szepet
Subscribers: rnkovacs, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D46950
llvm-svn: 333082
Add a helper test Fixture, so we can add tests which can check internal
attributes of AST nodes like getPreviousDecl(), isVirtual(), etc.
This enables us to check if a redeclaration chain is correctly built during
import, if the virtual flag is preserved during import, etc. We cannot check
such attributes with the existing testImport.
Also, this fixture makes it possible to import from several "From" contexts.
We also added several test cases here, some of them are disabled.
We plan to pass the disabled tests in other patches.
Patch by Gabor Marton!
Differential Revision: https://reviews.llvm.org/D43967
llvm-svn: 328906
