[tlbuild] dvibook failure on Cygwin

[Ken Brown]

On 2/25/2012 2:27 PM, Paul Vojta wrote:
> On Sat, Feb 25, 2012 at 01:30:47PM -0500, Ken Brown wrote:
>> On 2/25/2012 11:45 AM, Ken Brown wrote:
>>> On 2/24/2012 6:01 PM, Ken Brown wrote:
>>>> On 2/24/2012 5:35 PM, Karl Berry wrote:
>>>>> Hi Ken,
>>>>>
>>>>> Something is seriously wrong with getopt (from kpathsea) on Cygwin.
>>>>>
>>>>> And always has been, and just never been noticed before?
>>>>> Possible, I suppose, but doesn't seem especially likely.
>>>>
>>>> You're right, of course. I'm not seeing any problem except in dvibook.
>>>> But I have no idea what could be preventing getopt from working properly
>>>> in dvibook, and I can't make any sense out of what I saw under gdb.
>>>> Maybe Peter will think of something.
>>>
>>> Problem solved: the programs that use getopt need to include more
>>> kpathsea headers. I don't know yet exactly which one(s) or why, but I
>>> simply added `#include<kpathsea/kpathsea.h>' to dvibook.c (and the
>>> other files in the seetexk directory that use getopt), and now all tests
>>> pass.
>>>
>>> I'll look more carefully and figure out which header(s) are actually
>>> needed. I'll also check the rest of the texlive tree.
>>>
>>> Interestingly, adding this #include caused the familiar warning about
>>> the redeclaration of optarg, optind, etc., to appear in the compilation
>>> of these programs. Previously the warning wasn't there for the programs
>>> in seetexk.
>>>
>>> I'll send a patch once I have a clearer idea of what's going on.
>>
>> OK, it turns out that<kpathsea/c-unistd.h>  is the header that is
>> needed, and it is only needed because it includes the system header
>> <unistd.h>.  (The latter includes the system header<getopt.h>; this
>> explains the redeclaration warnings.)
>>
>> I don't understand why we need unistd.h (and why only on Cygwin) in
>> order for kpathsea's getopt to work right.  So I'll hold off on
>> sending a patch, in the hope that someone can explain this.
>>
>> Ken
>
> One possibility is that the sizes of the argument types in the prototype
> for getopt are different when c-unistd.h is included compared with when it
> is not.  Have you checked that?

That might be it.  The prototype for getopt in kpathsea/getopt.h doesn't 
even give the argument types except on systems that use the GNU C 
library.  In particular, it doesn't give the argument types on Cygwin.

Ken