The code in ASTContext::DeclMustBeEmitted was supposed to handle this,
but didn't take into account that synthesized members such as operator=
might not get marked as template specializations, because they're
synthesized on the instantiation directly when handling the class-level
dllexport attribute.
llvm-svn: 342240
With MSVC, PCH files are created along with an object file that needs to
be linked into the final library or executable. That object file
contains the code generated when building the headers. In particular, it
will include definitions of inline dllexport functions, and because they
are emitted in this object file, other files using the PCH do not need
to emit them. See the bug for an example.
This patch makes clang-cl match MSVC's behaviour in this regard, causing
significant compile-time savings when building dlls using precompiled
headers.
For example, in a 64-bit optimized shared library build of Chromium with
PCH, it reduces the binary size and compile time of
stroke_opacity_custom.obj from 9315564 bytes to 3659629 bytes and 14.6
to 6.63 s. The wall-clock time of building blink_core.dll goes from
38m41s to 22m33s. ("user" time goes from 1979m to 1142m).
Differential Revision: https://reviews.llvm.org/D48426
llvm-svn: 335466