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
A dllimport'd vtable always points one past the RTTI data, this means
that the initializer will never end up referencing the data. Our
emission is a harmless waste.
llvm-svn: 260062
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
There will be an explicit template instantiation in another translation
unit which will provide the definition of the VF/VB-Tables.
This fixes PR22932.
llvm-svn: 232680
Currently we emit DeferredDeclsToEmit in reverse order. This patch changes that.
The advantages of the change are that
* The output order is a bit closer to the source order. The change to
test/CodeGenCXX/pod-member-memcpys.cpp is a good example.
* If we decide to deffer more, it will not cause as large changes in the
estcases as it would without this patch.
llvm-svn: 226751
Previously, we would have a private backing variable and an internal
alias pointing at it.
However, -fdata-sections only fires if a global variable has non-private
linkage. This means that an unreferenced vftable wouldn't get
discarded, bloating the object file.
Instead, stick the backing variable in a comdat even if the alias has
internal linkage. This will allow the linker to drop the vftable if it
is unused.
llvm-svn: 212901
Comdat IR references were mistakenly printed for aliases when they
passed through the IR/AsmWriter code.
This makes clang's tests not check for the existance of these wrongly
printed comdat references.
llvm-svn: 212733
David Majnemer