port-powerpc/56892: powerpc ieeefp.h fails if _ISOC99_SOURCE is defined

[he%NetBSD.org@localhost]

>Number:         56892
>Category:       port-powerpc
>Synopsis:       powerpc ieeefp.h fails if _ISOC99_SOURCE is defined
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-powerpc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jun 19 17:25:00 +0000 2022
>Originator:     Havard Eidnes
>Release:        NetBSD 9.99.97
>Organization:
	I try...
>Environment:
System: NetBSD malus.urc.uninett.no 9.99.97 NetBSD 9.99.97 (MALUS) #22: Wed Jun  8 19:40:53 CEST 2022  he%malus.urc.uninett.no@localhost:/usr/obj/sys/arch/macppc/compile/MALUS macppc
Architecture: powerpc
Machine: macppc
>Description:
	
>How-To-Repeat:
	Try to build mach/py-scipy from pkgsrc, watch it fail with

/usr/include/ieeefp.h:15:9: error: unknown type name 'fp_rnd'
   15 | typedef fp_rnd fp_rnd_t;
      |         ^~~~~~
/usr/include/ieeefp.h:19:9: error: unknown type name 'fp_except'
   19 | typedef fp_except fp_except_t;
      |         ^~~~~~~~~

	For some reason, the build is done with -D_ISOC99_SOURCE.
	However, some folks told me that these parts of the float
	implementation is supposed to be part of ISO C99.  However,
	/usr/include/powerpc/ieeefp.h contains

#if !defined(_ISOC99_SOURCE)

typedef int fp_except;

	and the fp_rnd define is similarly protected.

	The amd64 version of that file does not have this ifdef around
	these definitions.

	Not entirely sure who is right or wrong...

>Fix:
	Perhaps move those definitions outside of the ifdef, or remove
	the ifdef entirely?