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Date:   Mon, 21 Mar 2022 12:39:05 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Stephen Rothwell <sfr@canb.auug.org.au>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
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        rick.p.edgecombe@intel.com, rppt@kernel.org,
        linux-toolchains@vger.kernel.org, Andrew.Cooper3@citrix.com,
        ndesaulniers@google.com
Subject: Re: linux-next: build warnings after merge of the tip tree
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On Mon, 21 Mar 2022 12:22:59 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> Or maybe another solution is:
> 
> funcA:
> 	[..]
> 	jmp funcB
> 	call __fexit__
> 	ret
> 
> And if funcA is being traced, we change jmp to a call.
> 
> 	[..]
> 	call funcB
> 	call __fexit__

We could also make __fexit__ a tail call:

> 	ret


funcA:
	[..]
	call funcB
	jmp __fexit__

We would also need a way to know that funcA has a tail call at the end. So
more help from either the compiler or objtool.

-- Steve