glibc 2.18 freeze!

[Roland McGrath]

> If __attribute__ ((optimize ("no-tree-loop-distribute-patterns"))) works
> on older compilers with nor warning or error then that should also work.
> I forgot we could use an attribute here.

You need a configure check.  e.g. 4.4 supports __attribute__ ((optimize))
but doesn't grok that particular option, so it says:
	o.c:2: error: unrecognized command line option "-fno-tree-loop-distribute-patterns"
for:
	__attribute__ ((optimize ("no-tree-loop-distribute-patterns")))
	void foo (void) {}