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Date: Tue, 29 Mar 2016 20:58:38 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Dimitry Andric <dim@FreeBSD.org>
Cc: Andriy Gapon <avg@FreeBSD.org>, freebsd-toolchain@FreeBSD.org
Subject: Re: warning: DWARF2 only supports one section per compilation unit
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On Tue, Mar 29, 2016 at 07:49:14PM +0200, Dimitry Andric wrote:
> These are harmless, and have been showing up for at least a year now.
> Clang is just notifying you that due to DWARF2 limitations, it will not
> emit debug info for more than one code section.
> 
> All such warnings in our tree are about artificially added sections,
> such as .note.GNU-stack, .reloc and __xen_guest, and it is not likely
> that anybody cares that those sections will not have debug info.
> 
> Lastly, I never found an option to shut up the warnings.  Well, apart
> from using -gdwarf-4. :-)

.note.GNU-stack should not have any content at all.  Issuing the warning
for empty section is pointless, and it would hide in the noise a real
bug if anything migrates under the section.