On 4 January 2017 at 16:10, Jonathan Wakely <jwak...@redhat.com> wrote: > On 04/01/17 16:00 +0100, Christophe Lyon wrote: >> >> Hi Jonathan, >> >> On 4 January 2017 at 12:02, Jonathan Wakely <jwak...@redhat.com> wrote: >>> >>> On 03/01/17 15:32 +0000, Jonathan Wakely wrote: >>>> >>>> >>>> Here's what I plan to commit to trunk tomorrow. >>> >>> >>> >>> Committed to trunk. >>> >>> >> After this commit (r244051), I do see improvements, but also a few new >> failures. >> The big picture is at >> >> http://people.linaro.org/~christophe.lyon/cross-validation/gcc/trunk/244051/report-build-info.html >> >> Where the expected improvements for arm-none-eabi, with default cpu&fpu >> are: >> >> http://people.linaro.org/~christophe.lyon/cross-validation/gcc/trunk/244051/arm-none-eabi/diff-libstdc++-rh60-arm-none-eabi-default-default-default.txt >> >> New failures appear when forcing -march=armv5t in runtestflags (the 3 >> red items in the 1st report): >> >> - FAIL appears [ => FAIL]: >> >> 18_support/exception_ptr/60612-terminate.cc execution test >> 18_support/exception_ptr/60612-unexpected.cc execution test >> 30_threads/packaged_task/members/at_thread_exit.cc execution test >> 30_threads/promise/members/at_thread_exit.cc execution test >> >> Note that in these cases we are compiling the test cases with >> -march=armv5t, but link >> with libraries built --with-cpu=cortex-a9, so there might be a mismatch? > > > Yes, this is probably the same issue as PR63829
Indeed. > > Richard's comment on the bug report says that arm should always use > atomics, via kernel helpers if necessary, so that there is no ABI > change when using -march for older CPUs. > > I don't know how to do that, but I hope we can make some progress on > it for gcc 8. > That would be good, maybe Richard can post an example in bugzilla? Thanks, Christophe
