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From: "markus at oberhumer dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/95903] New: gcc 10: wrong code with -fwrapv Date: Thu, 25 Jun 2020 23:25:40 +0000 [thread overview] Message-ID: <bug-95903-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95903 Bug ID: 95903 Summary: gcc 10: wrong code with -fwrapv Product: gcc Version: 10.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: markus at oberhumer dot com Target Milestone: --- Link at Compiler Explorer: https://godbolt.org/z/VgNLcX The following 2 functions should generate identical code when using "-fwrapv", but the second function is missing the sign extension after the add. // compile with: gcc-10 -m64 -O2 -fwrapv char get_byte_use_add(const char* ptr, int off) { off += 1; return ptr[off]; } char get_byte_use_plus(const char* ptr, int off) { return ptr[off + 1]; // gcc: BUG }
next reply other threads:[~2020-06-25 23:25 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-06-25 23:25 markus at oberhumer dot com [this message] 2020-06-26 6:30 ` [Bug middle-end/95903] " jakub at gcc dot gnu.org 2020-06-26 7:41 ` markus at oberhumer dot com 2020-06-26 8:05 ` jakub at gcc dot gnu.org 2020-06-26 8:35 ` markus at oberhumer dot com 2020-06-26 8:56 ` jakub at gcc dot gnu.org 2020-06-26 10:38 ` markus at oberhumer dot com 2020-06-26 11:03 ` jakub at gcc dot gnu.org 2020-06-26 11:17 ` markus at oberhumer dot com 2020-06-26 11:36 ` markus at oberhumer dot com 2020-06-27 10:42 ` cvs-commit at gcc dot gnu.org 2020-06-29 9:35 ` cvs-commit at gcc dot gnu.org 2020-09-16 19:22 ` cvs-commit at gcc dot gnu.org 2020-09-17 17:55 ` jakub at gcc dot gnu.org
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