Normally, in MinGW mode, inline methods aren't dllexported.
However, in the case of a dllimported template instantiation,
the inline methods aren't instantiated locally, but referenced
from the instantiation. Therefore, those methods also need to
be dllexported, in the case of an instantiation.
GCC suffers from the same issue, reported at [1], but the issue
is still unresolved there.
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89088
Differential Revision: https://reviews.llvm.org/D61176
llvm-svn: 359343
An explicit template instantiation declaration used to let
callers assume both outer and nested classes instantiations were
defined in a different translation unit.
If the instantiation is marked dllexport, only the outer class
is exported, but the caller will try to reference the instantiation
of both outer and inner classes.
This makes MinGW mode match both MSVC and Windows Itanium, by
having instantations only cover the outer class, and locally emitting
definitions of the nested classes. Windows Itanium was changed to
use this behavious in SVN r300804.
This deviates from what GCC does, but should be safe (and only
inflate the object file size a bit, but MSVC and Windows Itanium
modes do the same), and fixes cases where inner classes aren't
dllexported.
This fixes missing references in combination with dllexported/imported
template intantiations.
GCC suffers from the same issue, reported at [1], but the issue
is still unresolved there. The issue can probably be solved either
by making dllexport cover all nested classes as well, or this
way (matching MSVC).
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89087
Differential Revision: https://reviews.llvm.org/D61175
llvm-svn: 359342
Contrary to MSVC, GCC/MinGW needs to have the dllexport attribute
on the template instantiation declaration, not on the definition.
Previously clang never marked explicit template instantiations as
dllexport in MinGW mode, if the instantiation had a previous
declaration, regardless of where the attribute was placed. This
makes Clang behave like GCC in this regard, and allows using the
same attribute form for both MinGW compilers.
This fixes PR40256.
Differential Revision: https://reviews.llvm.org/D61118
llvm-svn: 359285