Rename C files to .c in GCC source

[Joseph Myers]

On Tue, 3 Feb 2015, Jonny Grant wrote:

> > There are around 11k files that have the .C ending to them; all in the
> > testsuite.  I don't think it make sense to move them.
> 
> How many minutes labor is this task?

It's desirable for test names to be stable so that results can be compared 
over time, which means a presumption that renaming an existing testcase is 
bad unless the name is really, really confusing (a pair testname-1.c and 
testname_1.c might count as confusing, but not test.C unless there's 
another very similar test in the same directory, in which case the "test" 
part would need changing).

-- 
Joseph S. Myers
joseph@codesourcery.com