This reverts commit r260449.
We would supress our emission of vftable definitions if we thought
another translation unit would provide the definition because we saw an
explicit instantiation declaration. This is not the case with
dllimport, we want to synthesize a definition of the vftable regardless.
This fixes PR26569.
llvm-svn: 260548
Referencing a dllimported vtable is impossible in a constexpr
constructor. It would be friendlier to C++ programmers if we
synthesized a copy of the vftable which referenced imported virtual
functions. This would let us initialize the object in a way which
preserves both the intent to import functionality from another DLL while
also making constexpr work.
Differential Revision: http://reviews.llvm.org/D17061
llvm-svn: 260388
Summary:
The vtable takes its DLL storage class from the class, not the key
function. When they disagree, the vtable won't be exported by the DLL
that defines the key function. The easiest way to ensure that importers
of the class emit their own vtable is to say that the class has no key
function.
Reviewers: hans, majnemer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D11913
llvm-svn: 244488
MinGW has some pretty strange behvaior around RTTI and
dllimport/dllexport:
- RTTI data is never imported
- RTTI data is only exported if the class has no key function.
llvm-svn: 244266
Note: __declspec is also temporarily enabled when compiling for a CUDA target because there are implementation details relying on __declspec(property) support currently. When those details change, __declspec should be disabled for CUDA targets.
llvm-svn: 238238
We would blindly assume that RTTI data should have the same linkage as
the vtable because we didn't think the RTTI data was external. This
oversight stemmed because we didn't take dllimport into account.
This fixes PR21512.
llvm-svn: 221511
The Itanium rules are not appropriate for the MS ABI. RTTI data is
_never_ imported and thus is never available_externally. It is either
internal (if the type's linkage is internal) or linkonce_odr.
This also means that classes which inherit from dllimport'd bases force
their translation unit to duplicate the entirety of the RTTI data of
that base.
Interestingly, the complete object locator can never be referenced by
translation units which import the class.
This fixes PR20106.
llvm-svn: 212256
David Majnemer