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From: "npl at chello dot at" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/65945] New: ARM: unaligned access when stroing nullptr Date: Thu, 30 Apr 2015 10:08:00 -0000 [thread overview] Message-ID: <bug-65945-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65945 Bug ID: 65945 Summary: ARM: unaligned access when stroing nullptr Product: gcc Version: 4.8.4 Status: UNCONFIRMED Severity: major Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: npl at chello dot at Target Milestone: --- Created attachment 35429 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35429&action=edit code causing the issue Hello, the attachedcode produces an unaligned access for arm, on the production code I ran into this issue with versions 5.1, 4.9.2, 4.8.4. This reduced testcase doesnt produce the issue with 5.1, but for 4.9.2 and 4.8.4. The issue seems to be the line constexpr inline_type bool operator ==(bitmask X, decltype(nullptr)) \ { return X == bitmask(); } aparrently gcc converts stores the given parameter on the frame without caring for alignment ("str r3, [fp, #-25]"). changing the type to unsigned seems to fix this Commandline to reproduce: arm-none-eabi-g++ -std=c++11 -O0 -c unalignedgcc.cpp
next reply other threads:[~2015-04-30 10:08 UTC|newest] Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-04-30 10:08 npl at chello dot at [this message] 2015-04-30 10:09 ` [Bug c++/65945] " npl at chello dot at 2015-04-30 10:13 ` npl at chello dot at 2015-04-30 11:29 ` [Bug c++/65945] C++ alignment of nullptr_t is 1 and might cause unaligned stores to the frame redi at gcc dot gnu.org 2015-04-30 13:47 ` npl at chello dot at 2015-04-30 13:57 ` npl at chello dot at 2015-04-30 14:30 ` pinskia at gcc dot gnu.org 2015-04-30 20:27 ` npl at chello dot at 2015-05-22 18:20 ` foom at fuhm dot net 2015-05-25 13:23 ` ebotcazou at gcc dot gnu.org 2015-06-04 21:32 ` foom at fuhm dot net 2015-06-19 14:08 ` foom at fuhm dot net 2015-07-01 17:07 ` jason at gcc dot gnu.org 2015-07-01 17:59 ` jason at gcc dot gnu.org 2015-07-01 18:01 ` jason at gcc dot gnu.org 2015-07-01 18:07 ` jason at gcc dot gnu.org 2015-07-10 11:08 ` npl at chello dot at
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