standards/51416: Missing new C11 headers (stdalign.h and others)

[coypu%sdf.org@localhost]

>Number:         51416
>Category:       standards
>Synopsis:       Missing new C11 headers (stdalign.h and others)
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    standards-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Aug 16 02:25:00 +0000 2016
>Originator:     coypu
>Release:        NetBSD 7.99.35
>Organization:
>Environment:
NetBSD laptop 7.99.35 NetBSD 7.99.35 (GENERIC) #2: Mon Aug 15 20:16:12 IDT 2016  fly@laptop:/home/fly/obj/sys/arch/amd64/compile/GENERIC amd64

>Description:
Now we have C11 support but not all the headers to go along with it, so
packages correctly test for C11 before including them, which we pass,
but fail to include, breaking builds.

example: new math/py-pytables fails:

/* If C11 is supported, use it's built-in aligned allocation. */
#if __STDC_VERSION__ >= 201112L
  #include <stdalign.h>
#endif

and in build:

c-blosc/blosc/blosc.c:63:24: fatal error: stdalign.h: No such file or directory
>How-To-Repeat:

>Fix: