Slight recoding of util.c:repeatcpy() to circumnavigate

Slight recoding of util.c:repeatcpy() to circumnavigate
a Digital C compiler optimizer bug that broke the 'x'
operator under certain circumstances.  See t/op/repeat.t
test #20 for graphic details.  Reported in

From: Gisle Aas <gisle@aas.no>
To: Mark Martinec <Mark.Martinec@nsc.ijs.si>
Cc: ach@xray.mpe.mpg.de, cpan-testers@perl.org, perl5-porters@perl.org
Subject: Re: Digest-MD5-2.00 test fails on DEC Alpha - a patch
Date: 18 Dec 1998 14:27:40 +0100
Message-ID: <m37lvpa8c3.fsf@furu.g.aas.no>

and discussed further in the thread

From: Jarkko Hietaniemi <jhi@iki.fi>
To: Gisle Aas <gisle@aas.no>
Cc: Mark Martinec <Mark.Martinec@nsc.ijs.si>, ach@xray.mpe.mpg.de,
        cpan-testers@perl.org, perl5-porters@perl.org
Subject: x operator broken in DEC Alpha for 8-bit characters (Re: Digest-MD5-2.00 test fails on DEC Alpha - a patch)
Date: Fri, 18 Dec 1998 16:18:37 +0200 (EET)
Message-ID: <13946.25661.193449.138023@alpha.hut.fi>

p4raw-id: //depot/cfgperl@2498