Re: defined(FOO) in macros

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Article #4349

#4349

From: John Rickard
Date: Sat, 11 Nov 1995 17:34

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Colin Plumb (colin@nyx10.cs.du.edu) wrote:

: Now, the second two diagnostics are fine, but is the compiler allowed to
: not recognize "defined(FOO)" when it appears as part of a macro expansion?

Yes.  6.8.1 (about #if directives) says that macro expansion is done
on the expression (except that macro names that are the argument of
"defined" are not expanded), and "if the token *defined* is generated
as a result of this replacement process [...] the behaviour is
undefined".

-- 
John Rickard

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Path: arc1-ca.pugleaf.net!news.atml.co.uk!jrr
From: jrr@atml.co.uk (John Rickard)
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Subject: Re: defined(FOO) in macros
Date: 11 Nov 1995 17:34:58 GMT
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