> -----Original Message----- > From: gcc-ow...@gcc.gnu.org [mailto:gcc-ow...@gcc.gnu.org] On Behalf Of > Ian Lance Taylor > Sent: 14 June 2010 05:43 > To: David Brown > Cc: gcc@gcc.gnu.org > Subject: Re: Issue with LTO/-fwhole-program > > David Brown <david.br...@hesbynett.no> writes: > > > After doing a bit more reading and thinking, it seems to me that > > -fwhole-program will be used in most cases where LTO is used. You > use > > -flto when compiling each source file, then link them with gcc with > > -flto and -fwhole-program. Except in the case of libraries or other > > files which need external symbols, you will want that combination to > > generate optimal code. So if this combination alone, without common > > symbols, is going to cause problems, then this would be a much bigger > > issue than if it is only triggered by common symbols. > > That scenario is fine. > > You can look back to see the problematic case posted earlier. It was > a case where one file was compiled with -flto, one file was compiled > without -flto, both files defined a common symbol with the same name, > the object files were linked together using -flto -fwhole-program, and > the gold plugin was not used. All elements are essential to recreate > the problem.
Actually, gold plugin is used in the original example. However, resolution produced by plugin is bypassed due to a bug-fix by Richard. Do you have any comment on that: http://gcc.gnu.org/ml/gcc-patches/2010-06/msg01116.html Bingfeng
