On Tue, Apr 25, 2017 at 4:52 PM, Jakub Jelinek <ja...@redhat.com> wrote: > Hi! > > A severe ABI bug on AArch64 and especially on ARM 32-bit has been > recently discovered and GCC 7.1 is going to have that ABI change in. > For details see http://gcc.gnu.org/PR77728 > gcc-7.1.1-0.16.fc{26,27} which I'll build tomorrow will contain the > ABI changes as well as a -Wpsabi diagnostics (note:) on code that is > changing the ABI. > The ABI change should affect primarily just C++ code passing PODs
By primarily is it guaranteed to be limited to C++ or is it possible it could affect other code? > by value where all the non-static data members and base classes are at most > word aligned, but there are some static data members with doubleword > or bigger alignment or there are typedefs or other nested types in > the class/struct which are doubleword or bigger aligned, and are passed > in certain positions in the argument list (passing them in even registers > is fine, passing them in odd ones changes ABI, on the stack at odd positions > might change the ABI too). For the typedefs, the broken ABI of GCC 5.2 to > 7.0.1 > has been actually not even self-consitent in some templates, earlier > instantiation vs. lack thereof could affect the ABI. GCC 5.1 and earlier > for structs used to match earlier AAPCS version and had different rules and > issues. > > Could somebody from rel-eng perform a test mass rebuild on armv7hl > and aarch64 of F26 to determine which packages are affected by the > ABI changes so that we could rebuild only those that actually need changing? > > If grepping for note: is not good enough for the test mass rebuild, I could > hack up a test compiler that does something different when it encounters > this (say abort if it encounters this and some special env var is set, > or writes something into some /tmp/ file and let some brp script collect > info from there, etc.). > > Jakub > _______________________________________________ > devel mailing list -- devel@lists.fedoraproject.org > To unsubscribe send an email to devel-le...@lists.fedoraproject.org _______________________________________________ devel mailing list -- devel@lists.fedoraproject.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org
