configure fails to determine working strncmp

[Dmitry G. Baksheyev]

Dear Sir,

I am building binutils on Solaris 5.8:

% gzip -dc binutils-2.11.2.tar.gz | tar -xvpf -
% md b-build
% cd b-build
% ../binutils-2.11.2/configure --program-prefix=g --enable-shared --without-gcc 
--verbose

Configuring for a sparc-sun-solaris2.8 host.
...
checking for working mmap... yes
...
Configuring libiberty...
loading cache ../config.cache
checking host system type... sparc-sun-solaris2.8
checking build system type... sparc-sun-solaris2.8
...
checking for working mmap... (cached) yes
checking for working strncmp... no                      <=== cannot agree!!

====
The problem seems to come from incorrectly called mmap in
binutils-2.11.2/libiberty/aclocal.m4. My man mmap says:

     When MAP_ANON is set in flags, and fd is set to  -1,  mmap()
     provides  a  direct  path  to  return anonymous pages to the
     caller.  This operation is equivalent to passing  mmap()  an
     open  file descriptor on /dev/zero with MAP_ANON *elided* from
     the flags argument.
     ...
errno is set to EINVAL when
           MAP_ANON was specified, but the  file  descriptor  was
           not -1.

And look at the code from aclocal.m4:   

#ifndef MAP_ANON                /* MAP_ANON is defined */
#ifdef MAP_ANONYMOUS
#define MAP_ANON MAP_ANONYMOUS
#else
#define MAP_ANON MAP_FILE
#endif
#endif
/*...*/
  p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE,
                     MAP_ANON|MAP_PRIVATE, dev_zero, 0);
  if (p == (char *)-1)
    exit (2);           /* conftest exits here without checking strncmp */
/*...*/


Best wishes.
Dmitrii Baksheyev.