Hi Arnaud, On 29 Mar 2015, at 19:43, Arnaud Charlet wrote:
>> Currently Ada bootstrap is broken for bootstrap compiler == gcc-trunk, and >> platform == powerpc-darwin9 (although it is possible to bootstrap with >> gcc-4.9). >> >> The reason is that generations of sinfo.h appears now to _require_ support >> for atomics (I assume that's intended). > > No, that's definitely not intended, and I doubt this is the case since there > are other platforms without atomic support. > >> In fact, w.r.t atomics there's no need to treat powerpc-darwin any >> differently from other ppc platform. >> >> The patch below enables them which restores bootstrap and fixes 15 acts and 8 >> gnat regressions (which essentially, leaves GCC trunk on parity with >> gcc-4.9 for Ada on the powerpc-darwin9 platform). >> >> This is a bootstrap fail, albeit for an unmentioned target - however, it is >> entirely local to the platform, so >> OK for trunk? > > OK on principle, but that doesn't explain the underlying issue you got, > since atomics should definitely not be needed for bootstrap. > > Can you give more details on the failure you got? recent trunk (say 221750) built without the patch, is installed and then used as the bootstrap compiler. At stage #1 the following fail occurs when xsinfo is run to generate sinfo.h: (cd ada/bldtools/sinfo; gnatmake -q xsinfo ; ./xsinfo sinfo.h ) raised PROGRAM_ERROR : s-atocou.adb:57 explicit raise Looking at this code, it indicates that it is a dummy implementation for platforms without an atomic increment support. hence, I concluded (possibly erroneously) that such support is now required in some way. We can try and analyse further (slowish hardware), if necessary - but this is repeatable on two different setups. thanks Iain
