Jakub Jelinek wrote: > On Wed, Jul 09, 2014 at 02:19:36PM -0400, David Edelsohn wrote: > > > This is an ABI change for the affected corner cases of the ELFv2 > > > ABI. However, those cases should be extremely rare; the full > > > compat.exe and struct-layout-1.exp ABI compatibility test suite > > > passed, with the exception of two tests specifically intended > > > to test multiple homogeneous float aggregates. > > > > > > Tested on powerpc64le-linux. > > > > > > OK for mainline? > > > [ The patch should then also go into the 4.8 and 4.9 branches for > > > consistency. ] > > > > Okay everywhere. > > IMHO it should only go to the trunk, same as > https://gcc.gnu.org/ml/gcc-patches/2014-07/msg00540.html (see also related > PRs, has been discussed on IRC too). > > If it is a corner case, the better, fewer people will be affected when > transitioning from 4.9.x to 5.0 (or 4.10?). But 4.9.0 is for a few months > in the wild already, I don't think ABI changes are something people would > like to see between 4.9.0 and 4.9.1 or any other patchlevel revision, > most people aren't prepared to rebuild the world just because they have > upgraded to a newer compiler snapshot or new patchlevel version.
Richard Biener wrote: > Can you add -Wpsabi warnings for all the issues you found? That way > a world re-build will at least show if anything important is affected. OK, to summarize the off-line discussions on these concerns, what I'm now planning to do is the following: - Add -Wpsabi warnings for all cases changed to the mainline patch - Backport *only* the warnings, but not the actual change in behavior to the 4.8 and 4.9 branches. This should match existing precent of how to handle ABI changes. Doing a world-rebuild with the warnings enabled would certainly be extremely useful feedback ... Thanks, Ulrich -- Dr. Ulrich Weigand GNU/Linux compilers and toolchain ulrich.weig...@de.ibm.com
