Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!convex!news
From: dodson@convex.COM (Dave Dodson)
Newsgroups: comp.lang.fortran
Subject: Re: MS-FORTRAN bug in string concatenation
Message-ID: <1991Feb14.185049.3535@convex.com>
Date: 14 Feb 91 18:50:49 GMT
References: <2PWGG2@MPLVAX.SRI.COM>
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Reply-To: dodson@convex.COM (Dave Dodson)
Organization: Convex Computer Corporation; Richardson, TX
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In article <2PWGG2@MPLVAX.SRI.COM> HUESTIS@MPLVAX.SRI.COM (David L. Huestis) writes:
>Under Microsoft FORTRAN the following simple program
>
>       character string*4/'abc'/
>       string = '*'//string
>       write(*,*)string
>       end
>
>produces the output '**bb' while LAHEY and VAX yield '*abc'
>
>Microsoft FORTRAN takes no precautions against the source strings
>overlapping the destination string.

The above program is non-standard.  In a standard-conforming program, string
variables cannot appear on both the left- and right-hand side of an assignment
statement.  A Fortran compiler can do anything with a non-standard program,
including, but not restricted to, giving an error message, compiling and
giving some "reasonable" answer, or compiling and giving an unreasonable
answer.  Different implementations that compile and give some reasonable
result may choose different reasonable results.

----------------------------------------------------------------------

Dave Dodson		                             dodson@convex.COM
Convex Computer Corporation      Richardson, Texas      (214) 497-4234