buildworld fails with "Zero byte read from file, skipping rest of line"

[Gleb Smirnoff]

  Jeremie,

On Wed, Jan 15, 2014 at 08:40:53AM +0100, Jeremie Le Hen wrote:
J> > J>   ===> gnu/usr.bin/groff/src/libs/libgroff (all)
J> > J>   make[6]: "/usr/obj/usr/src.svn/tmp/usr/src.svn/gnu/usr.bin/groff/src/libs/libgroff/.depend" line 3: warning: Zero byte read from file, skipping rest of line.
J> > J>   make[6]: "/usr/obj/usr/src.svn/tmp/usr/src.svn/gnu/usr.bin/groff/src/libs/libgroff/.depend" line 3: Need an operator
J> > J>   make[6]: "/usr/obj/usr/src.svn/tmp/usr/src.svn/gnu/usr.bin/groff/src/libs/libgroff/.depend" line 4: Need an operator
J> > J>   make[6]: Fatal errors encountered -- cannot continue
J> > J>   make[6]: stopped in /usr/src.svn/gnu/usr.bin/groff/src/libs/libgroff
J> > J>   *** [all] Error code 1
J> > J> 
J> > J> Typscript available here:
J> > J> http://people.freebsd.org/~jlh/typescript.buildworld.txt
J> > J> 
J> > J> Any ideas?
J> > 
J> > Can you try to reproduce this with unmapped I/O turned off in boot loader?
J> 
J> I've never heard of that.  Can you please point me to the right
J> code/doc?

In loader prompt:

OK set vfs.unmapped_buf_allowed=0
OK boot

-- 
Totus tuus, Glebius.