Hello,

Since gdb 7.4.1 a PATH_MAX usage was introduced in the file
gdb/nto-tdep.c:nto_init_solib_absolute_prefix(). This function is only
called in gdb/nto-procfs.c. This file is QNX Neutrino specific and is
not compiled for Hurd (while nto-tdep.c, also QNX-specific is).

The attached patch solve_PATH_MAX_issue.patch fixes the FTBFS for
GNU/Hurd. Alternately the build should be changed to exclude compilation
of nto-tdep.c for non-QNX architectures. The compilation of various
targets specific code is enabled by --enable-targets=all in
the .../gdb/Makefile ALL_TARGET_OBS variable. This seems to be common of
builds for all architectures in Debian.

In case you need feedback from me use Cc: since I'm not subscribed to
gdb-patches.

Thanks,
Svante Signell