>Number:         3163
>Category:       port-sparc
>Synopsis:       errno.h multiple inclusion problem
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    gnats-admin (GNATS administrator)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 30 05:20:00 1997
>Last-Modified:
>Originator:     Paul Boven
>Organization:
----------------------------------------------------------------------
Paul Boven, <e.p.boven@student.utwente.nl>  PE1NUT  QRV 145.575 JO32KF
  Nothing would get done in the world, if we didn't have insomniacs.
           Or at least, nothing would get done at night. 
----------------------------------------------------------------------
>Release:        include.tar.gz from current, 4th jan 1997
>Environment:
System: NetBSD wit387304.student.utwente.nl 1.2B NetBSD 1.2B (ELC) #4: Sat Jan 18 17:44:10 CET 1997 paul@wit387304.student.utwente.nl:/usr/src/sys/arch/sparc/compile/ELC sparc

>Description:
When compiling a file that includes errno.h twice, a compilation error
results. The second inclusion of line 54 or /usr/include/errno.h conflicts
with the first one because somehow an extra "const" is generated.

c++ -c  -I. -I.. -I../liboctave -I../src -I../glob -I../libcruft/misc  -DHAVE_CONFIG_H  -fno-implicit-templates  -g -O2 -Wall file-ops.cc
In file included from safe-stat.h:30,
                 from file-ops.cc:47:
/usr/include/errno.h:54: conflicting types for `const char *const const sys_errlist[]'
/usr/include/errno.h:54: previous declaration as `const char * const sys_errlist[]'

This fails on NetBSD-sparc and on intel, so I suspect it's common to most 
NetBSD-platforms.

>How-To-Repeat:
I have tried to construct a simple example to trigger this problem, but just
including errno.h twice in a simple c-file does not trigger this effect.
The easiest way to reproduce this would be to ftp octave-2.0(.1) from a
local site or ftp.che.wisc.edu and unpack and ./configure it. Then cd to
the liboctave subdirectory and either "gnumake file-ops.o" or give the
command-line shown in the Description-field. (Don't use NetBSD-make).

>Fix:
The generation of an extra "const" might be a compiler-bug and is way
beyond me to fix. I`d _suggest_ protecting errno.h against multiple inclusion
via te normal _ERRNO_H #define and #ifdef-statements. Because of the somewhat
complicated nature of errno.h I haven't made an actual patch because I cannot
oversee where to put these lines so as not to break compilation for a lot of
other things.
>Audit-Trail:
>Unformatted: