Internal wrappers and _LIBC .vs. tests _of_ the headers as installed

[Zack Weinberg]

On Mon, Aug 22, 2016 at 5:58 PM, Joseph Myers <joseph@codesourcery.com> wrote:
> On Mon, 22 Aug 2016, Zack Weinberg wrote:
>> 3) What do you think is the most practical way to kludge together a
>> test mode that *does* match the behavior of the installed headers?
>> 3a) How exactly does conform/ deal with this?  I tried to read that
>> code and came up with "it doesn't", which must be wrong.
>
> conform/ (a) doesn't use any of the standard compilation rules, just
> $(CC), which avoids getting _LIBC defined, and (b) defines _ISOMAC, which
> the include/ wrappers are supposed to take to mean only to serve as
> wrappers for the installed header (needed, because many of the installed
> headers are in subdirectories not searched when building in other
> subdirectories) and not to include any internal declarations.

Thanks, that was exactly the hint I needed.  Patches coming up :)

zw