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Date: Tue, 23 Mar 2021 21:17:09 -0400
From: Mike Frysinger <vapier@gentoo.org>
To: Peng Yu <pengyu.ut@gmail.com>
Cc: noloader@gmail.com, libc-help <libc-help@sourceware.org>
Subject: Re: Does glibc has complete test coverage?
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On 23 Mar 2021 18:09, Peng Yu wrote:
> On Tue, Mar 23, 2021 at 4:02 PM Jeffrey Walton wrote:
> > On Tue, Mar 23, 2021 at 4:43 PM Mike Frysinger wrote:
> > > also try googling for "100% test coverage" and reading the variety of
> > > opinions the wider world has on the topic.
> 
> https://blog.ndepend.com/aim-100-percent-test-coverage/
> 
> I don't think the so-called "The Diminishing Returns Argument" is
> valid. When you have too many branches to test which rarely occurs in
> practice, this just indicates the code is badly structured. To have
> complete coverage, if the testing code is much more complex than the
> real code, this means that the real code should be restructured to
> make testing code simpler.

there are software ideals, and there's the real world.  glibc occupies
the latter.  you are welcome to submit patches to try and simplify the
code, but you will have to also not regress on performance, or overall
maintainability.  software engineering is about balancing all of these
conflicting requirements.
-mike