[RFC][BZ #16549] Add sanity check for condvar alignment.

[Joseph S. Myers]

On Tue, 11 Feb 2014, Florian Weimer wrote:

> I think the real issue here is our lack of error checking for the futex system
> call.  strace on the test case shows this:

I'm not sure what we would do with an error here.  Cf 
<https://sourceware.org/glibc/wiki/Style_and_Conventions#Invalid_pointers> 
noting that a crash or assertion failure on an invalid NULL pointer is 
better than returning an error value that would likely be ignored by the 
buggy caller (although it's not obvious to me that diagnosing a misaligned 
pointer through an assertion is worthwhile anyway).

-- 
Joseph S. Myers
joseph@codesourcery.com