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Date:   Wed, 29 Jan 2020 01:46:55 +0100 (CET)
From:   Jiri Kosina <jikos@kernel.org>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
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Subject: Re: [PATCH v3 5/6] x86/ftrace: Use text_poke()
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On Tue, 28 Jan 2020, Josh Poimboeuf wrote:

> > Anyway, I think that we might make your life easier with using the 
> > proposed -Wsuggest-attribute=noreturn.
> 
> Maybe.  Though if I understand correctly, this doesn't help for any of 
> the new warnings because they're for static functions, and this only 
> warns about global functions.

Could you please provide a pointer where those have been 
reported/analyzed?

For the cases I've seen so far, it has always been gcc deciding under 
certain circumstances not to propagate __attribute__((__noreturn__)) from 
callee to caller even in the cases when caller unconditionally called 
callee.

AFAIU, the behavior is (and always will) be dependent on the state of gcc 
optimizations, and therefore I don't see any other way than adding 
__noreturn anotation transitively everywhere in order to silence objtool.

So those cases have to be fixed anyway.

What are the other cases please? Either I have completely missed those, or 
they haven't been mentioned in this thread.

Thanks,

-- 
Jiri Kosina
SUSE Labs