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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	[thread overview]
Message-ID: <bug-100442-4-bgkrCyTREL@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-100442-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100442

--- Comment #4 from Andres Freund <andres at anarazel dot de> ---
> Ending up with an excessive range isn't uncommon in code that freely converts between signed and unsigned integers (e.g., by passing an int to a size_t argument) and involves conditionals like those in tsCompareString().  GCC must assume the signed integers may be negative and convert to very large positive values.  Changing tsCompareString() to take size_t arguments instead 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 "[18446744073709551612,
18446744073709551615]" doesn't sound right from the perspective a compiler
user, rather than compiler author. Clearly the lower bound isn't actually
18446744073709551612.

      parent reply	other threads:[~2022-02-15 22:54 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-06  6:09 [Bug c/100442] New: " andres at anarazel dot de
2021-05-06  8:54 ` [Bug tree-optimization/100442] " pinskia at gcc dot gnu.org
2021-05-06  9:45 ` andres at anarazel dot de
2021-05-06 15:39 ` msebor at gcc dot gnu.org
2022-02-15 22:54 ` andres at anarazel dot de [this message]

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