Re: Fix for _Complex_I problems

[Rainer Tammer]

Hello Greg,

Greg Troxel wrote:
> I cannot test on Solaris; I was reporting a problem that a pkgsrc user had.
>
> The fix looks like it will work, but I am not comfortable with it.  It
> mucks up the source with local defines to hack around lack of standards
> compliance.  Reading the second diff, there's much less of this.
>
> As far as I can tell, C99 says that if complex.h is there then
> _Complex_I has to work.  This is the reason why I'm being cranky about
> defining around it.
>
>   
On AIX _Complex_I is working if you use the IBM compiler (inline 
function). But if you use gcc then
you are doomed...
> I would prefer to use the compile test that you wrote, but to undefine
> HAVE_COMPLEX_H if it fails, thus falling back to not using the
> (therefore broken) complex support at all.  I had meant to suggest this,
> and I'm sorry if I didn't manage to do that.
>
> Adding a remedial
>
> #define _Complex_I 1.0fi
>
> to the beginning of numbers.c if _Complex_I weren't defined would seem
> less objectionable, and also work.
>
>   
On AIX:

complex.h:
#define complex    _Complex

/*.
* a constant expression of type const float _Complex with the
* value of the imaginary unit. (a number i such that i**2 =-1).
* __I is provided by the AIX xlc C99 compiler.
* WARNING: DO NOT USE __I DIRECTLY in an application. Always
* use _Complex_I .
*/
#define _Complex_I    __I

/*
* _Imaginary_I should be a constant expression of type
* const float _Imaginary with the value of the imaginary unit.
* This is optional in C99.
* This is not supported in the AIX xlc C99 compiler.
*/

/*.
* C99 requires this definition of the
* very common variable "I", to use as a simpler way
* to say _Complex_I. Mathematicians who would say
* "3i" will now say in C "3 * I".
*/
#undef I
#define I _Complex_I


> Thanks for paying attention to this.
>
>
>   
Bye
 Rainer