On Sun, 2013-10-20 at 23:44 +0200, Matthias Klose wrote: > Am 20.10.2013 22:58, schrieb Ben Hutchings: > > On Sun, 2013-10-20 at 22:21 +0200, Matthias Klose wrote: > >> Am 20.10.2013 00:25, schrieb Ben Hutchings: > >>> On Sat, 2013-10-19 at 23:38 +0200, Matthias Klose wrote: > >>>> Control: severity -1 important Control: tags -1 + moreinfo > >>>> > >>>>>> In file included from <command-line>:0:0: > >>>>>> /usr/include/stdc-predef.h:30:26: fatal error: bits/predefs.h: > >>>>>> No such file > >>>>> or directory > >>>>>> #include <bits/predefs.h> ^ > >>>>> compilation terminated. > >>>>> > >>>>> It looks like I can avoid this by changing the compile tests to > >>>>> use the -nostdinc option. But this change may possibly cause > >>>>> other problems, and neither the pre-included header nor the fact > >>>>> that -nostdinc disables it seem to be documented. > >>>> > >>>> please attach the test program and the command line options used for > >>>> this test case. I think the issue is within the kernel build system > >>>> not being prepared for multiarch and -nostdinc. > >>> > >>> gcc-4.8 -m64 -x c -c /dev/null > >> > >> works for me on a current sid/i386. I assume that gcc-4.8-multilib is > >> installed? > > > > No, it works if that's installed. But gcc-X.Y-multilib was previously only > > needed for building with a 64-bit C library, not for building a 64-bit > > kernel. > > > > If this kernel configuration was actually failing to build without > > gcc-4.8-multilib, I wouldn't mind so much. The problem is that it's built > > wrongly now. Maybe some later version of the kernel will be changed to > > detect or work around this problem, but we have to assume people will still > > try to build older versions not using -nostdinc for some time to come. > > Is this due to the missing /usr/include/asm symlink shipped in gcc-multilib? > It's not ideal, and I think I did file a bug report that this should be > shipped in one of the glibc packages, but can't find it anymore. The /usr/include/bits symlink in libc6-dev-amd64 is what makes this work again (which is disgusting, really...). Without that, stdc-predef.h can be found but not bits/predefs.h. > > The options to deal with this include: 1. Make missing headers non-fatal > > while pre-including <stdc-predef.h>. > > that would be the responsibility of those packages using non-standard options > like -nostdinc. Well the problem occurs because Linux uses -nostdinc only in the real compiles (so they succeed) but not the test compiles (so they fail). > > 2. Disable pre-inclusion of <stdc-predef.h>. > > no, done upstream to conform to standards. > > > 3. Make 32-bit gcc fail to compile anything with -m64 if gcc-X.Y-multilib > > is not installed, even if -nostdinc is used. > > welcome to multiarch, and thanks for upstreaming patches to fix these issues. > > > 4. Make gcc-X.Y depend on gcc-X.Y-multilib on architectures where it > > exists. > > well, then you can merge these again. the whole point to have them separate > were bug reports about being forced to install the non-defaults multilibs by > default. Indeed, I didn't say any of those options were good. > 5. Install the whole glibc headers into the multiarch header path. Would fix > some other things too, like allowing multiarch configurations for non-glibc > based triplets. And I assume it would allow your build to fail. I don't think this would help. Ben. -- Ben Hutchings Tomorrow will be cancelled due to lack of interest.
Attachment:
signature.asc
Description: This is a digitally signed message part