From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-470244-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 26017 invoked by alias); 11 Dec 2014 11:47:50 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Received: (qmail 25994 invoked by uid 48); 11 Dec 2014 11:47:47 -0000
From: "bernd.edlinger at hotmail dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/64265] New: r217669 broke tsan
Date: Thu, 11 Dec 2014 11:47:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 5.0
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: bernd.edlinger at hotmail dot de
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter attachments.created
Message-ID: <bug-64265-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2014-12/txt/msg01251.txt.bz2

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64265

            Bug ID: 64265
           Summary: r217669 broke tsan
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bernd.edlinger at hotmail dot de

Created attachment 34249
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34249&action=edit
test case

starting with r217669 tsan instrumentation gets wrong code:

g++ -g -fsanitize=thread test.cpp

./a.out

=> soaks all memory up.

reason is this function calls __tsan_func_entry in a loop:

_ZNSt12_Destroy_auxILb0EE9__destroyIN9__gnu_cxx17__normal_iteratorIPSsSt6vectorISsSaISsEEEEEEvT_S9_:
.LFB982:
        .loc 5 100 0
        .cfi_startproc
        pushq   %rbp
        .cfi_def_cfa_offset 16
        .cfi_offset 6, -16
        movq    %rsp, %rbp
        .cfi_def_cfa_register 6
        subq    $32, %rsp
        movq    %rdi, -16(%rbp)
        movq    %rsi, -32(%rbp)
.L153:
        movq    8(%rbp), %rax
        movq    %rax, %rdi
        call    __tsan_func_entry
        .loc 5 102 0 discriminator 2
        leaq    -32(%rbp), %rdx
        leaq    -16(%rbp), %rax
        movq    %rdx, %rsi
        movq    %rax, %rdi
        call   
_ZN9__gnu_cxxneIPSsSt6vectorISsSaISsEEEEbRKNS_17__normal_iteratorIT_T0_EESA_
        testb   %al, %al
        je      .L152
        .loc 5 103 0 discriminator 1
        leaq    -16(%rbp), %rax
        movq    %rax, %rdi
        call    _ZNK9__gnu_cxx17__normal_iteratorIPSsSt6vectorISsSaISsEEEdeEv
        movq    %rax, %rdi
        call    _ZSt11__addressofISsEPT_RS0_
        movq    %rax, %rdi
        call    _ZSt8_DestroyISsEvPT_
        .loc 5 102 0 discriminator 1
        leaq    -16(%rbp), %rax
        movq    %rax, %rdi
        call    _ZN9__gnu_cxx17__normal_iteratorIPSsSt6vectorISsSaISsEEEppEv
        jmp     .L153
.L152:
        .loc 5 104 0
        call    __tsan_func_exit
        leave
        .cfi_def_cfa 7, 8
        ret
        .cfi_endproc


it is generated from bits/stl_container.h, line 95-105:

template<bool>
  struct _Destroy_aux
  {
    template<typename _ForwardIterator>
      static void
      __destroy(_ForwardIterator __first, _ForwardIterator __last)
      {
        for (; __first != __last; ++__first)
          std::_Destroy(std::__addressof(*__first));
      }
  };