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From: Eric Botcazou <ebotcazou@libertysurf.fr>
To: richard.sandiford@arm.com
Cc: Jonathan Wakely <jwakely@redhat.com>, gcc-bugs@gcc.gnu.org,
 haoxintu@gmail.com
Subject: Re: How GCC treats ice-on-invalid-code?
Date: Thu, 02 Jul 2020 10:51:23 +0200
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> You mean, an ICE is perfectly valid as the first (and obviously then
> only) error diagnostic the compiler prints for =E2=80=9Cgarbage input=E2=
=80=9D?
> If so, I don't think that's true.  What counts as =E2=80=9Cgarbage=E2=80=
=9D seems
> a bit too subjective for that anyway.

When the input is totally nonsensical, e.g. generated by a machine for the=
=20
sole purpose of torturing the compiler, an ICE is good enough and IMO the b=
ug=20
report should essentially be ignored.  We have hundreds of open bug reports=
=20
for perfectly sensible code and any of them should have higher priority.

> E.g. deleting a chunk of lines from a file creates something that makes
> no sense and might be considered garbage, but that can easily happen
> with a botched resolution to a merge conflict (or being too trigger-happy
> with git rerere :-)).  I don't think it's OK for the compiler simply to
> crash without first giving the user an idea of what's wrong.

Sure, if the input originally comes from a real program, it's not garbage.

=2D-=20
Eric Botcazou