Re: good c compiler

jacob navia wrote, On 27/09/08 08:20:
lawrence.jones@xxxxxxxxxxx wrote:
jacob navia <jacob@xxxxxxxxxx> wrote:
MSVC users never use long double since it is the same as double,

And nobody ever uses long since it is the same as int on most platforms,
right?

And if they would use it, it will not port to lcc-win. As you know, long double
can be bigger than double.

My point was about compatibility between compilers on the same platform and that people need to be aware of where there are incompatibilities.

But can you point me to a header that is supposed to compile
under MSVC that uses long double? There is a lot of public domain
software that compiles under MSVC. Please find one.

It's C++ rather than C, but...
http://www.physionet.org/challenge/2006/sources/yuriy-chesnokov/lib.h

So there is your one example of someone providing a library including header file using long double. Of course finding such things is hard because of all the other stuff searches will throw up so I'm not going to search further.


MSVC stopped using long double since at least 10 years.

Still incorrect. It has long double it just uses the same representation as double. However, other people are complaining (with justification) that it does not use a higher precision long double.

Of course you can throw around ironic remarks like that as
long as you wish, together with your friends. Fact is,
MSVC doesn't even use long double.

Still incorrect. It supports long double, it just happens to use the same representation as double for it.

Anyway, the question was whether other people use long double in libraries that could be built with MSVC, and I've found one that is. There are valid reasons for doing this (making best use of the target platform) and these apply to closed source libraries as well as open source code.

I still say you have good reason for making long double higher precision. For all I know unlike with some other compilers you provide no compatibility with libraries built with MSVC, I just assumed your users might want to be able to use third-party pre-built libraries, since I know that I do, and in that case they need to be aware of any compatibility issues.

Other compiler vendors deliberately make themselves compatible with MSVC. If you choose not to that is up to you and does not affect your conformance to the C standard.
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