On Fri, Nov 8, 2019 at 10:17 PM Ryan Schmidt <[email protected]> wrote:
> On Nov 8, 2019, at 20:03, Joshua Root wrote: > > > On 2019-11-9 10:28 , Jack Howarth wrote: > >> I just noticed a really bizarre aspect to this Xcode 11 bug. If you > >> build gmp manually from source with the default compiler flags in use... > >> > >> ./configure > >> make > >> make check > >> > >> the t-powm test case fails. However if you add -fstack-check > >> explicitly on CFLAGS and CXXFLAGS, the t-powm test case failure is > >> suppressed. > >> > >> ./configure CFLAGS='-O2 -fcheck-stack' CXXFLAGS='-O2 -fcheck-stack' > >> make > >> make check > > > > Are the default compiler flags '-O2'? > > MacPorts default optimization flag is -Os. > > Same behavior... ./configure CFLAGS='-Os -fstack-check' CXXFLAGS='-Os -fstack-check' make make check suppresses the failure PASS: t-powm with Xcode 11.2 in a manual build. Wonder how many of the remaining packages that are requiring -fno-check-stack could actually be 'fixed' by explicitly passing -fcheck-stack instead. Obviously that option disabled some of the problematic stack checking code that Apple's clang is automatically generating in the absence of the flag.
