Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings

From	Jeff Merkey <linux.mdb@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings
Date	2016-02-12 05:30 +0100
Message-ID	<r1dwJ-1Tq-3@gated-at.bofh.it> (permalink)
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> In your case, for example, I looked through several dozen warnings,
> and they were ***all*** bogus.  Keep in mind that this might make me
> less inclined to pay attention to complaints from you in the future.
> The story of the buy who cried wolf too often comes to mind.
>
> Perhaps you could actually take a close look at the warnings, before
> you fire off an e-mail?  If at least one of the warnings were valid
> and pointed at an actual bug, it wouldn't have been a complete waste
> of my time....
>

I did take a close look at some of them (I reviewed them in assembler
-- probably a closer look than you gave them) and it was somewhat
confusing since the compiler was outputing jmp labels in the wrong
places in the code after I removed the calls to unreachable().

Ted, that's the problem with sitting around looking at C code all day
trying to find bugs created by the linux macros with assembler output
that does not map precisely to the C code.  I discovered this grepping
around in the assembler output of these macro H libs.

If you like I can go over all the garbage assembler this gcc issue
generates around these BUG() macros with calls to unreachable which is
why I raised the issue.

Jeff

Thread

[BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-11 04:20 +0100
  Re: [BUG REPORT] use of unreachable() masks uninitialized variables  warnings Theodore Ts'o <tytso@mit.edu> - 2016-02-11 15:10 +0100
    Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-11 19:20 +0100
      Re: [BUG REPORT] use of unreachable() masks uninitialized variables  warnings Theodore Ts'o <tytso@mit.edu> - 2016-02-12 03:50 +0100
        Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-12 05:20 +0100
        Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-12 05:30 +0100
          Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-12 05:50 +0100
        Re: [BUG REPORT] use of unreachable() masks uninitialized variables warnings Jeff Merkey <linux.mdb@gmail.com> - 2016-02-12 06:00 +0100

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