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From: "andres at anarazel dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/100442] Spurious -Wstringop-overread error
 with odd boundaries
Date: Tue, 15 Feb 2022 22:54:55 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D100442

--- Comment #4 from Andres Freund <andres at anarazel dot de> ---
> Ending up with an excessive range isn't uncommon in code that freely conv=
erts between signed and unsigned integers (e.g., by passing an int to a siz=
e_t argument) and involves conditionals like those in tsCompareString().  G=
CC must assume the signed integers may be negative and convert to very larg=
e positive values.  Changing tsCompareString() to take size_t arguments ins=
tead of int avoids the warning:

That true - and I agree that that code isn't great.

But the warning message is quite confusing: A bound of "[184467440737095516=
12,
18446744073709551615]" doesn't sound right from the perspective a compiler
user, rather than compiler author. Clearly the lower bound isn't actually
18446744073709551612.=