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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug debug/103241] Odd 0 length entries in location lists
Date: Tue, 16 Nov 2021 14:11:00 +0000	[thread overview]
Message-ID: <bug-103241-4-2YLT9D9dHE@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103241-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103241

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
We'd need preprocessed source + full gcc command line to investigate particular
cases, but generally, gcc itself doesn't often know that the range is zero
length, it has two labels that mark the start and end of the range.  If it is
the same labels, obviously it knows it is zero length range and can drop it,
but if it is different labels, it is harder or impossible (consider e.g. inline
asm in between, the inline asm could expand to zero instructions or zero
instructions in the current section (.pushsection, emit something elsewhere,
.popsection), or even just asm ("") - gcc intentionally doesn't try to
understand what inline asm does.

  reply	other threads:[~2021-11-16 14:11 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-15  1:17 [Bug debug/103241] New: " wcohen at redhat dot com
2021-11-16 14:11 ` jakub at gcc dot gnu.org [this message]
2021-11-16 14:46 ` [Bug debug/103241] " wcohen at redhat dot com
2021-11-16 14:51 ` wcohen at redhat dot com
2021-11-16 15:11 ` marxin at gcc dot gnu.org
2021-11-16 15:24 ` wcohen at redhat dot com
2021-11-16 15:39 ` marxin at gcc dot gnu.org
2021-11-16 16:18 ` wcohen at redhat dot com
2021-11-18 10:24 ` marxin at gcc dot gnu.org
2021-11-18 10:35 ` jakub at gcc dot gnu.org
2021-11-18 15:11 ` wcohen at redhat dot com
2021-11-18 15:23 ` jakub at gcc dot gnu.org
2021-11-18 16:00 ` wcohen at redhat dot com
2021-11-18 16:18 ` jakub at gcc dot gnu.org
2021-11-19 10:18 ` aoliva at gcc dot gnu.org

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