Compiler segfault when building the kernel

[Celejar <celejar@gmail.com>]

Hi,

I've been building kernels (vanilla from upstream) for years with
kernel-package (typical command line: "time make-kpkg -j2 --initrd
--revision 1.custom kernel_image"; .kernel-pkg.conf contains just the
line "root_cmd = fakeroot") without problem. Recently, the builds have
begun to fail with messages like these:

*****

> In file included from ./include/linux/percpu-rwsem.h:8:0,
>                  from ./include/linux/fs.h:30,
>                  from ./include/linux/pagemap.h:8,
>                  from block/partitions/check.h:1,
>                  from block/partitions/msdos.c:23:
> ./include/linux/rcu_sync.h:29:48: internal compiler error: Segmentation fault
>  enum rcu_sync_type { RCU_SYNC, RCU_SCHED_SYNC, RCU_BH_SYNC };
>                                                 ^
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <file:///usr/share/doc/gcc-4.9/README.Bugs> for instructions.
>   CC      fs/posix_acl.o
> The bug is not reproducible, so it is likely a hardware or OS problem.

*****

> In file included from ./include/linux/linkage.h:6:0,
>                  from ./include/linux/kernel.h:6,
>                  from ./include/linux/list.h:8,
>                  from ./include/linux/module.h:9,
>                  from lib/fonts/font_8x16.c:8:
> ./include/linux/export.h:63:22: internal compiler error: Segmentation fault
>   static const struct kernel_symbol __ksymtab_##sym  \
>                       ^
> ./include/linux/export.h:93:25: note: in expansion of macro ‘___EXPORT_SYMBOL’
>  #define __EXPORT_SYMBOL ___EXPORT_SYMBOL
>                          ^
> ./include/linux/export.h:97:2: note: in expansion of macro ‘__EXPORT_SYMBOL’
>   __EXPORT_SYMBOL(sym, "")
>   ^
> lib/fonts/font_8x16.c:4633:1: note: in expansion of macro ‘EXPORT_SYMBOL’
>  EXPORT_SYMBOL(font_vga_8x16);
>  ^
> Please submit a full bug report,
> with preprocessed source if appropriate.

This occurred immediately following a cleaning of the source tree
("make-kpkg ... clean"), the first one I've done in quite some time, so
I'm pretty sure that that's what triggered this, whatever the
underlying problem actually is.

Googling suggests that this sort of thing can be triggered by race
conditions caused by build systems improper handling of
concurrency,e.g.:

https://askubuntu.com/questions/343490/the-bug-is-not-reproducible-so-it-is-likely-a-hardware-or-os-problem

For the last year or so, I've been building with -j2, so I tried again
without it. I still got the same error, but when I once again did a
clean and then rebuilt without -j2, the build succeeded.

Any ideas? Is this a bug I should be filing against kernel-package (or
anywhere else)?

Celejar