Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ames!mailrus!uflorida!novavax!proxftl!bill
From: bill@proxftl.UUCP (T. William Wells)
Newsgroups: comp.lang.c
Subject: Re: Duff's device
Message-ID: <718@proxftl.UUCP>
Date: 7 Sep 88 14:25:41 GMT
References: <32941@cca.CCA.COM>
Reply-To: bill@proxftl.UUCP (T. William Wells)
Organization: Proximity Technology, Ft. Lauderdale
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In article <32941@cca.CCA.COM> g-rh@CCA.CCA.COM (Richard Harter) writes:
: Now all us good children know that when we write a loop with conditionals
: the compiler does some magic for us -- it creates some labels and transfers
: and tests and maybe does some block allocation.  And it is incumbent upon
: us not to confuse the compiler.  If I declare some variables at the start
: of the loop are they going to be there when I jump into the middle?  This
: is the sort of code that you have to be a language lawyer to be sure that
: it works right -- and you have to assume that the compiler writer was a
: good language lawyer too.  I don't like to write code that requires being
: a language lawyer to read and verify; life is too short.

Pardon, but the question of what happens to local variables when
entering a loop from other than the top has never been an obscure
issue in C.  Both K&R and ANSI assert that the locals will *not*
be initialized, and K&R implies and ANSI explicitly states that
the memory for the locals will be allocated.

I also don't know of any compiler that fails to allocate space in
this situation.  Does anyone know of any?

---
Bill
novavax!proxftl!bill