Hi! On Sat, Mar 27, 2021 at 04:07:18PM +0100, Florian Weimer wrote: > * Michael Meissner via Gcc-patches: > > On Wed, Feb 24, 2021 at 11:12:54PM +0000, Joseph Myers wrote: > >> This change appears to have broken builds for powerpc in a configuration > >> that bootstraps a cross toolchain starting with a GCC build with no libc > >> available. > >> > >> Specifically, such a bootstrap build uses --disable-decimal-float among > >> other options (in the first GCC build before libc has been built), to > >> disable GCC target library code that has any dependence on libc or libc > >> headers - dfp-bit.c uses libc headers, without an inhibit_libc > >> conditional, so cannot be used in such a bootstrap configuration. Most of > >> the DFP code in libgcc is disabled by --disable-decimal-float, but it > >> seems the new conversions are not. This results in errors of the form: > >> > >> In file included from > >> /scratch/jmyers/glibc-bot/src/gcc/libgcc/config/rs6000/_kf_to_sd.c:37: > >> /scratch/jmyers/glibc-bot/src/gcc/libgcc/dfp-bit.c:32:10: fatal error: > >> stdio.h: No such file or directory > >> 32 | #include <stdio.h> > >> | ^~~~~~~~~ > >> compilation terminated. > >> > >> The appropriate fix is not to build any of these new conversions in the > >> --disable-decimal-float case. (That clearly makes sense anyway, even in > >> the absence of the bootstrap issue.) > >> > >> https://sourceware.org/pipermail/libc-testresults/2021q1/007576.html > > > > Thanks. I agree if --disable-decimal-float is used we should not build the > > conversions. And we want to eliminate the stdio.h dependency. I will look > > at > > it unless somebody has already fixed it. > > This issue is still present. > > What about the patch below? > > Thanks, > Florian > > rs6000: Do not build _Float128/Decimal routines with --disable-decimal-float > > Fixes commit 781183595acba67a37c66f59a0c1d9b5fee7e248 ("Add conversions > between _Float128 and Decimal.).
That seems likely. Okay for trunk if Mike agrees. Thanks! Segher > libgcc/ > * config/rs6000/t-float128 (fp128_ppc_funcs): Add decimal floating > point functions for $(decimal_float) only.
