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From: "richard.purdie at linuxfoundation dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug other/108464] [13 Regression] Broken -fdebug-prefix-map since
 r13-3599
Date: Thu, 19 Jan 2023 13:21:35 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108464

--- Comment #1 from Richard Purdie <richard.purdie at linuxfoundation dot o=
rg> ---
I can see why that would change behaviour with the patch :(.

It is a tough dilemma since without the patch, files might have prefixes
removed some of the time but not all the time, depending on whether they we=
re
accessed via a symlink (or similar) or not. It was effectively impossible to
remap some prefix values meaning in some cases output files couldn't be bui=
ld
deterministically.

One possible way to fix this issue might be to call realpath on DW_AT_comp_=
dir
so that we're always working on canonicalized paths? I'm not sure if that w=
ould
be acceptable or not, the challenge right now is that we're making comparis=
ons
against things which aren't always definitive.=