[mythtv] [mythtv-commits] Ticket #9426: MacOS X symbols missing
Michael T. Dean
mtdean at thirdcontact.com
Sat Jan 22 22:13:21 UTC 2011
On 01/22/2011 03:11 PM, MythTV wrote:
> #9426: MacOS X symbols missing
>
>
> Comment (by Dave Morrison<dave@…>):
>
> Replying to [comment:12 stuarta]:
> > I'm not seeing this on Snow Leopard with the current XCode toolset.
> > What is it you are running on?
>
> 10.5.8 with gcc 4.0.1. I see the following in the development notes for
> gcc 4.2:
Our code in mythexp.h checks GCC version and defines MPUBLIC to
__attribute__((visibility("default"))) for GCC >= 4, which matches up
with our configure check for symbol visibility. That said, symbol
visibility on x86_64 failed to really work properly until 4.2 (vanilla,
but RH backported the fixes to RH GCC 4.1.1, and other distros may have
done the same--but I doubt Apple is). The problem was with handling of
relocatable code.
When we switched to symbol visibility as a default, I didn't think
anyone was still using such ancient versions of GCC, so I didn't think
there'd be problems.
Perhaps we should do a check for GCC 4.2+ in configure's
gxx/symbol_visibility check and update mythexp.h. That would disable it
even on x86_32 for old GCC, but we've really made it default mainly for
devs to catch issues before pushing them.
See http://www.gossamer-threads.com/lists/mythtv/users/241504#241504 for
details of the bugs.
Mike
More information about the mythtv-dev
mailing list