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From: chris@trantor.umd.edu (Chris Torek)
Newsgroups: comp.lang.c
Subject: #pragma
Message-ID: <2765@umd5.umd.edu>
Date: 23 May 88 14:44:55 GMT
References: <54080@sun.uucp> <11608@mimsy.UUCP> <7950@brl-smoke.ARPA> <1988May23.012636.1719@utzoo.uucp>
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Reply-To: chris@trantor.umd.edu (Chris Torek)
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In article <1988May23.012636.1719@utzoo.uucp> henry@utzoo.uucp
(Henry Spencer) writes:
>...  Compilers are required to ignore unrecognized #pragmas
>(although I for one think a warning message is in order...) ....
>The description [in the dpANS] of #pragma just says "causes the
>implementation to behave in an implementation-defined manner".

I took advantage of that clause to make a version of cpp which
warns about #pragma.  The reasoning works as follows:  The
`implementation-defined' manner can be almost anything (GNU cpp
runs rogue, which appears to be perfectly legal), so long as the
compiler `recognises' the #pragma.  Hence we simply `recognise' it
by (in theory) comparing it with a regular expression---to wit,
`.*'---and print `#pragma noticed and nothing else done' as our
implementation-defined action.
-- 
In-Real-Life: Chris Torek, Univ of MD Computer Science, +1 301 454 7163
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