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Re: [RFC][BZ #15799] Make div cross-platform.


On Fri, 25 Oct 2013, Ondrej Bilka wrote:

> On Fri, Oct 25, 2013 at 08:09:20PM +0000, Joseph S. Myers wrote:
> > On Fri, 25 Oct 2013, Ondrej Bilka wrote:
> > 
> > > Hi, following bug report complains that division does not satisfy c
> > > standard.
> > 
> > The bug report is about code that can never be executed - that is, the 
> > logic errors in it are of no significance.  Everything after the 
> > assignments to result.quot and result.rem, except for the return 
> > statement, should just be deleted as irrelevant given C99 semantics for 
> > division, and those assignments should be left unchanged.  This should be 
> > done for all of div, ldiv and lldiv.  This code is not shared with gnulib, 
> > so random C90 compilers are irrelevant to it.
> > 
> Then close that bug as invalid.

It's a perfectly valid bug report of useless and confusing code in the 
glibc source code, just like a report of spelling errors in the sources is 
valid.  I agree with the statement in the bug that "This means that 
div(numer, denom) should simply return the results of numer / denom and 
numer % denom directly (C99 section 7.20.6.2), and the old incomplete 
run-time test-and-adjustment code (and the obsolete comment block) should 
be removed entirely.".  It simply isn't *user-visible* (which means (a) no 
need to add testcases when fixing it, (b) if it hadn't already been 
reported in Bugzilla, there would be no need for anyone fixing it to file 
a bug there).

-- 
Joseph S. Myers
joseph@codesourcery.com


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