[Patch] Fix HP_SMALL_TIMING_AVAIL undef warnings

[Joseph S. Myers]

On Mon, 28 Apr 2014, Will Newton wrote:

> This looks like it is the right thing to do, however I believe the
> warnings will persist on:
> 
> ia64
> x86_64
> i386
> powerpc32
> powerpc64
> sparc32
> sparc64
> 
> Which all use their own hp-timing.h.

Indeed.  For such a patch you need to:

* Work out what header should define the macro.

* Ensure that it does define the macro, for all configurations of glibc.

* Go through all uses of the macro that test #ifdef / #ifndef / #if 
defined / #elif defined, and change them to use #if conditionals.  Make 
sure that all the users include the relevant header before the tests.  If 
some don't include the header, there may be pre-existing bugs from testing 
whether a macro is defined without including the header that defines it - 
in which case you need (a) to work out whether the test in the file is 
actually correct, or if it is bitrotten, and (b) to call out these cases 
in the patch submission, giving your analysis of whether the test is 
actually correct or not.

-- 
Joseph S. Myers
joseph@codesourcery.com