RFA: PATCH to ipa-devirt for c++/58678

[Jason Merrill]

The failure with -flto is due to make_decl_local clearing DECL_COMDAT, 
so the check in ipa_devirt allows devirtualization to an implicitly 
declared destructor.  It's not clear to me why make_decl_local needs to 
clear DECL_COMDAT, but it's simpler to just remove that check from 
ipa_devirt.

Tested x86_64-pc-linux-gnu.  OK for trunk and 4.9?
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 58678-5.patch
Type: text/x-patch
Size: 1226 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/gcc-patches/attachments/20140910/dd21d1a6/attachment.bin>