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=head1 NAME

perlirix - Perl version 5 on Irix systems

=head1 DESCRIPTION

This document describes various features of Irix that will affect how Perl
version 5 (hereafter just Perl) is compiled and/or runs.

=head2 Building 32-bit Perl in Irix

Use

	sh Configure -Dcc='cc -n32'

to compile Perl 32-bit.  Don't bother with -n32 unless you have 7.1
or later compilers (use cc -version to check).

(Building 'cc -n32' is the default.)

=head2 Building 64-bit Perl in Irix

Use

	sh Configure -Dcc='cc -64' -Duse64bitint

This requires require a 64-bit MIPS CPU (R8000, R10000, ...)

You can also use

	sh Configure -Dcc='cc -64' -Duse64bitall

but that makes no difference compared with the -Duse64bitint because
of the C<cc -64>.

You can also do

	sh Configure -Dcc='cc -n32' -Duse64bitint

to use long longs for the 64-bit integer type, in case you don't
have a 64-bit CPU.

If you are using gcc, just

	sh Configure -Dcc=gcc -Duse64bitint

should be enough, the Configure should automatically probe for the
correct 64-bit settings.

=head2 About Compiler Versions of Irix

Some Irix cc versions, e.g. 7.3.1.1m (try cc -version) have been known
to have issues (coredumps) when compiling perl.c.  If you've used
-OPT:fast_io=ON and this happens, try removing it.  If that fails, or
you didn't use that, then try adjusting other optimization options
(-LNO, -INLINE, -O3 to -O2, et cetera).  The compiler bug has been
reported to SGI.  (Allen Smith <easmith@beatrice.rutgers.edu>)

=head2 Linker Problems in Irix

If you get complaints about so_locations then search in the file
hints/irix_6.sh for "lddflags" and do the suggested adjustments.
(David Billinghurst <David.Billinghurst@riotinto.com.au>)

=head2 Malloc in Irix

Do not try to use Perl's malloc, this will lead into very mysterious
errors (especially with -Duse64bitall).

=head2 Building with threads in Irix

Run Configure with -Duseithreads which will configure Perl with
the Perl 5.8.0 "interpreter threads", see L<threads>.

For Irix 6.2 with perl threads, you have to have the following
patches installed:

        1404 Irix 6.2 Posix 1003.1b man pages
        1645 Irix 6.2 & 6.3 POSIX header file updates
        2000 Irix 6.2 Posix 1003.1b support modules
        2254 Pthread library fixes
        2401 6.2 all platform kernel rollup

B<IMPORTANT>: Without patch 2401, a kernel bug in Irix 6.2 will cause
your machine to panic and crash when running threaded perl.  Irix 6.3
and later are okay.

    Thanks to Hannu Napari <Hannu.Napari@hut.fi> for the IRIX
    pthreads patches information.

=head2 Irix 5.3

While running Configure and when building, you are likely to get
quite a few of these warnings:

  ld:
  The shared object /usr/lib/libm.so did not resolve any symbols.
        You may want to remove it from your link line.

Ignore them: in IRIX 5.3 there is no way to quieten ld about this.

During compilation you will see this warning from toke.c:

  uopt: Warning: Perl_yylex: this procedure not optimized because it
        exceeds size threshold; to optimize this procedure, use -Olimit
        option with value >= 4252.

Ignore the warning.

In IRIX 5.3 and with Perl 5.8.1 (Perl 5.8.0 didn't compile in IRIX 5.3)
the following failures are known.

 Failed Test                  Stat Wstat Total Fail  Failed|Failing List
 -----------------------------------------------------------------------
 ../ext/List/Util/t/shuffle.t    0   139    ??   ??       %  ??
 ../lib/Math/Trig.t            255 65280    29   12  41.38%  24-29
 ../lib/sort.t                   0   138   119   72  60.50%  48-119
 56 tests and 474 subtests skipped.
 Failed 3/811 test scripts, 99.63% okay. 78/75813 subtests failed,
    99.90% okay.

They are suspected to be compiler errors (at least the shuffle.t
failure is known from some IRIX 6 setups) and math library errors
(the Trig.t failure), but since IRIX 5 is long since end-of-lifed,
further fixes for the IRIX are unlikely.  If you can get gcc for 5.3,
you could try that, too, since gcc in IRIX 6 is a known workaround for
at least the shuffle.t and sort.t failures.

=head1 AUTHOR

Jarkko Hietaniemi <jhi@iki.fi>

Please report any errors, updates, or suggestions to
L<https://github.com/Perl/perl5/issues>.