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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/115160] Enabling undefined behaviour sanitizer causes or'ed bit shift to report wrong result
Date: Tue, 21 May 2024 09:53:12 +0000	[thread overview]
Message-ID: <bug-115160-4-X9Wl1wF0lZ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-115160-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115160

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
There is no sequence point analyzer in any compiler I'm aware of and I think it
would be extremely hard to implement that.
GCC has -Wsequence-point warning, which can handle lots of cases, but with the
C++ abstractions the front-end can't really know what the different function
calls will do and whether they have some undesirable side-effects or not.
With the pointers, the compiler sees the post-increment operations, with
overloaded operators it doesn't, it sees calls to some operator and it doesn't
know what the operator will do.  Those functions could be pure and not change
anything on the shared object, or they can change it.

  parent reply	other threads:[~2024-05-21  9:53 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-20 10:03 [Bug c++/115160] New: " raanan.lori at getnexar dot com
2024-05-20 17:56 ` [Bug c++/115160] " jakub at gcc dot gnu.org
2024-05-21  9:41 ` raanan.lori at getnexar dot com
2024-05-21  9:53 ` jakub at gcc dot gnu.org [this message]
2024-05-21 10:07 ` raanan.lori at getnexar dot com
2024-05-21 11:46 ` redi at gcc dot gnu.org
2024-05-21 12:09 ` jakub at gcc dot gnu.org

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