[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: AC_TRY_LINK not correct
From: |
Paul Eggert |
Subject: |
Re: AC_TRY_LINK not correct |
Date: |
Thu, 06 May 2004 16:35:36 -0700 |
User-agent: |
Gnus/5.1006 (Gnus v5.10.6) Emacs/21.3 (gnu/linux) |
Kean Johnston <address@hidden> writes:
> It is a perfectly valid thing for an OS to use #define to implement
> some function in terms of another.
Sure, but (with a few well-defined exceptions, like 'assert' and
'isinf') implementations are required to supply a function as well.
> For example, to implement isinf() in terms of a call to fpclassify().
'isinf' is required to be a macro, so it doesn't make much sense to
use AC_TRY_LINK to test for its existence.
For macros like 'isinf', probably the best way is to avoid Autoconf
entirely and just use something like '#ifdef isinf'.