On Sat, Nov 12, 2016 at 1:00 PM, John David Anglin <dave.anglin@xxxxxxxx> wrote: > I'm thinking about adding a "-mabi=" option to change the call ABI. Currently, objects larger than 64 bits > in the 32-bit runtime are passed by reference and the callee copies the object when necessary. This is > opposite to x86 where the caller does the copies. Most targets are caller copies. > > The problem with callee copies is that it doesn't work with openmp. There are race problems and sometimes > we get internal compiler errors with openmp code due to this problem. This became apparent when new testcases > were added to gcc-6. It's tough to fix this problem in gcc. > > This is gcc PR: > <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68733>. > > This is fixed if we change abi to caller copies (maybe "-mabi=gnu" and "-mabi=hp"). The default could be set > by a configure options. Probably, we would want the new gnu abi on linux as the default. However, there is > the potential to break stuff during the migration to the new abi. > > Opinions? I think this is a good idea. Anything that brings us slowly towards parity with other arches is better in the long-run. Any idea how to test the impact? Cheers, Carlos. -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
