[PATCH] clang-cl: Only mark dllexported constexpr functions once

[Ehsan Akhgari]

================
Comment at: lib/Sema/SemaDeclCXX.cpp:4745
@@ -4744,1 +4744,3 @@
       if (MD->isUserProvided()) {
+        // Don't mark constexpr functions again
+        if (MD->isConstexpr())
----------------
hans wrote:
> ehsan wrote:
> > hans wrote:
> > > The comment is a little vague (and should end with a period). Maybe something like "constexpr functions are already marked referenced."
> > > 
> > > Also, David pointed out that this does not only apply to user-defined functions, so it should be moved back to where you first suggested in the PR. Sorry for my misleading suggestion here before.
> > What about http://llvm.org/bugs/show_bug.cgi?id=21718#c6?
> Maybe what we should do is something like
> 
> if (MD->isReferenced())
>   continue;
> 
> Would that pass all the old tests and your new one?
That doesn't fix the original issue.

http://reviews.llvm.org/D6528