[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: AC_C_LONG_DOUBLE is obsolescent.

From: Bob Friesenhahn
Subject: Re: AC_C_LONG_DOUBLE is obsolescent.
Date: Wed, 9 Apr 2008 14:43:24 -0500 (CDT)

On Wed, 9 Apr 2008, Eric Blake wrote:

According to Bob Friesenhahn on 4/9/2008 12:35 PM:
| I am confused since I don't see how the usefullness of this test can be
| obsolescent.

The test was merely whether compilers support the type 'long double'; as
all modern compilers obey this part of the C standard, it is no longer
worth checking whether long double is syntactically valid, and rather just
assuming that it is.

I always assumed that the test worked as described and verified that 'long double' has more range than 'double'. It seemed to be doing more than ensure that the compiler does not choke when requested to provide 'long double'. My application only uses 'long double' for cumulative addition so it does not require much support from the math library. I have yet to encounter a problem with a system which passes the long double test.

You have now used the term "modern compilers" which I assume means C'99 rather than C'89?

Yes, current systems is intended to mean any system that an autoconf
configure script will run on.  It excludes platforms like Solaris 4, which
are no longer supported by the vendor.

Solaris 8 is the oldest version of Solaris supported by Sun, however, I see no reason why Solaris 2.1 should not be able to execute current autoconf. Perhaps it might need to be augmented with a newer shell and a few updated utilities. The founding principle of autoconf is "feature based testing" and I hope that this principle is not going away any time soon. I have some 10 year old systems here which are still running strong and still just as useful with running their respective applications as the day they were built. If I was to upgrade their OS they would no longer be useful.

Bob Friesenhahn
GraphicsMagick Maintainer,

reply via email to

[Prev in Thread] Current Thread [Next in Thread]