INSTALL should tell about particular systems

[Bruno Haible]

Hi,

Over and over again users on HP-UX and Tru64 stumble upon compilation failures
of GNU packages that are due to their use of broken vendor-installed C 
compilers.
Examples are these threads:
  http://lists.gnu.org/archive/html/bug-gnulib/2008-04/msg00065.html (HP-UX)
  http://lists.gnu.org/archive/html/bug-gnulib/2006-08/msg00023.html (OSF/1)
Can we add some recommendations about it in the INSTALL file? I would suggest
a section like this, between the sections "Optional Features" and
"Specifying the System Type".

----------------------------------------------------------------------------
Particular Systems
==================

   On HP-UX, the default C compiler is not ANSI C compatible.  If GNU CC
is not installed, it is recommended to use the following options in order
to use an ANSI C compiler:

     ./configure CC="cc -Ae"

and if that doesn't work, install pre-built binaries of GCC for HP-UX.

   On OSF/1 a.k.a. Tru64, some versions of the default C compiler don't grok
its <wchar.h> header file.  The option -nodtk can be used as a workaround.
If GNU CC is not installed, it is therefore recommended to try

     ./configure CC="cc"

and if that doesn't work, try

     ./configure CC="cc -nodtk"
-----------------------------------------------------------------------------

The INSTALL file in GNU gettext also contains similar advice about AIX 3 and
BeOS, but I think these platforms are not used by many people any more
nowadays.

Bruno