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From: shenkin@cunixf.cc.columbia.edu (Peter S. Shenkin)
Newsgroups: comp.lang.fortran
Subject: Re: COMMON and SAVE statements
Message-ID: <1990Aug6.145839.23660@cunixf.cc.columbia.edu>
Date: 6 Aug 90 14:58:39 GMT
References: <65861@lll-winken.LLNL.GOV>
Reply-To: shenkin@cunixf.cc.columbia.edu (Peter S. Shenkin)
Organization: Columbia University
Lines: 19

In article <65861@lll-winken.LLNL.GOV> ray@rogue.llnl.gov writes:
>2. What could possibly be the motivation for the standard allowing
>   variables in COMMON to be become undefined without a SAVE statement?

This would allow  storage taken up by COMMON blocks not currently in use to
be used for other purposes;  eg, to store automatic variables in other 
functions, or to store active COMMON blocks.

I believe that the standard requires COMMON blocks to be saved until the
entire tree of functions using them has exited;  thus COMMON blocks declared
in MAIN will be saved without an explicit SAVE anyway.  Would someone out there
more knowledgable than I please correct me if I am incorrect, or confirm this
if I am correct?

	-P.
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Peter S. Shenkin, Department of Chemistry, Barnard College, New York, NY  10027
(212)854-1418  shenkin@cunixc.cc.columbia.edu(Internet)  shenkin@cunixc(Bitnet)
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