[BuildTools] Question regarding header and type detection in CoinUtils

[Miles Lubin]

<cstdint> is the standard C++ header file for int64_t. Are there platforms
we support where this header doesn't exist?

On Fri, Oct 3, 2014 at 11:24 AM, Stefan Vigerske <stefan at math.hu-berlin.de>
wrote:

> Hi,
>
> defining and exporting COINUTILS_HAS_CINTTYPES and
> COINUTILS_HAS_INTTYPES_H and thus including the (c)inttypes(.h) header in
> CoinTypes.h sounds best to me.
> It's a bit complicated, as we already have HAVE_CINTTYPES and
> HAVE_INTTYPES_H, but it seems to be clean and safe.
>
> While doing so, you could then also introduce COINUTILS_HAS_CSTDINT :-).
> COINUTILS_HAS_STDINT_H was indeed added a year ago to fix some specific
> issues.
>
> Stefan
>
>
>
> On 10/03/2014 04:47 PM, Ted Ralphs wrote:
>
>> Hi everyone,
>>
>> This e-mail is probably directed mostly at Stefan, but if anyone else has
>> an opinion, feel free to weigh in.
>>
>> I'm trying to build CoinAll with Visual Studio 9 (we still need to support
>> it because of Python extensions) on a new laptop running Windows 8 that
>> also has Visual Studio 12 installed (yes, I know I'm asking for trouble).
>> For reasons I cannot discern, the compiler is using a combination of the
>> headers from both compiler versions (9 and 12), which may or may not be
>> related to the issues I'm seeing. In a nutshell, code that builds fine on
>> my old laptop now fails to build with the exact same compiler.This has
>> caused me to dig into some stuff that I found does not completely make
>> sense to me.
>>
>> The problem arises from the check for the type int64_t in the configure
>> script for CoinUtils, which is done as so.
>>
>> AC_CHECK_TYPE([int64_t],[CoinInt64=int64_t ; CoinUInt64=uint64_t],[],[
>> #ifdef HAVE_CINTTYPES
>> # include <cinttypes>
>> #else
>> # ifdef HAVE_INTTYPES_H
>> #  include <inttypes.h>
>> # endif
>> #endif
>> ])
>>
>> The type int64_t is found at configure time (I think in the header
>> cintypes), but only because the inttypes headers have been manually
>> included for the test. In CoinTypes.hpp, these headers are *not* currently
>> included and thus, the type is not found at compile time, which leads to
>> an
>> error.
>>
>> Adding the same block of code from the test above to CoinTypes.hpp fixes
>> the problem for CoinUtils, but building Cbc then fails because the symbols
>> HAVE_CINTTYPES and HAVE_INTTYPES_H are not exported to config_coinutils.h.
>> If I export the symbols
>>
>> COINUTILS_HAS_CINTTYPES
>> COINUTILS_HAS_INTTYPES_H
>>
>> then everything is fine. I have no idea why this was working fine in the
>> recent past and now it suddenly causes a problem or why everything is fine
>> on Linux and OS X. I suppose that type must be found in a different header
>> on those OS's.
>>
>> Now my questions:
>>
>> 1. Another solution would be to check for the type int64_t without
>> including the headers manually, which would then not require including
>> them
>> in CoinTypes.hpp. We would then just use long long instead of int64_t I
>> suppose. I don't think this is the right solution, but I wanted to see if
>> anyone had a different opinion.
>>
>> 2. This all made me realize that we have a block like this in
>> CoinTypes.hpp.
>>
>> #ifdef COINUTILS_HAS_STDINT_H
>> #include <stdint.h>
>> #endif
>>
>> Why do we only check for stdint.h and not cstdint (as we do with
>> inttypes).
>> With the Visual Studio build, it is finding cstdint, not stdint.h, but
>> then
>> not including it. Of course, this is not causing a problem at the moment,
>> but should we also export COINUTILS_HAS_CSTDINT? I haven't checked for
>> blame, but I'm sure that code was inserted in there to solve some specific
>> issue with finding types on some platform, but I guess that it would be
>> more portable and correct if cstdint were also included when it's
>> available.
>>
>> If you read this far, let me know what you think and sorry for the long
>> and
>> detailed mail!
>>
>> Cheers,
>>
>> Ted
>>
>>
>>
>> _______________________________________________
>> BuildTools mailing list
>> BuildTools at list.coin-or.org
>> http://list.coin-or.org/mailman/listinfo/buildtools
>>
>>
> _______________________________________________
> BuildTools mailing list
> BuildTools at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/buildtools
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/buildtools/attachments/20141003/0b715215/attachment.html>