This is the mail archive of the gcc-bugs@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug c++/66774] New: Any optimization causes segfault on binary


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66774

            Bug ID: 66774
           Summary: Any optimization causes segfault on binary
           Product: gcc
           Version: 5.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: contact at tobast dot fr
  Target Milestone: ---

Created attachment 35916
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35916&action=edit
Source code that fails when optimized, .ii file.

Hello,

When I run the binary produced by compiling the attached code (which *waits for
two integers on its stdin before actually running*, eg. 2000 100000) is
executed, it results in a segfault when any optimization level is enabled
(tested with -O1, -O2, -O3), while it's fine with -O0. As the bug does not
occur with -O0 I assume the bug is part of gcc, and not of my own code, but I
could obviously be wrong.

Apparently, when compiled with both -O2 and -g, then ran through gdb, the
segfault comes from the "push" line 12620 of the .ii file, but only after a few
pushes happened (?!).

The exact command line used for compilation is:
$ g++ -Wall -Wextra -O[opt level] [optionnaly -g] code.cpp
No warning is raised.

My machine runs Archlinux, kernel 4.0.7-2-ARCH, I use the default gcc package
from this distribution, and $ g++ -v gives

--------
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-unknown-linux-gnu/5.1.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: /build/gcc-multilib/src/gcc-5-20150623/configure --prefix=/usr
--libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man
--infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --enable-libmpx --with-system-zlib --with-isl
--enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object
--enable-linker-build-id --enable-lto --enable-plugin
--enable-install-libiberty --with-linker-hash-style=gnu
--enable-gnu-indirect-function --enable-multilib --disable-werror
--enable-checking=release --with-default-libstdcxx-abi=c++98
Thread model: posix
gcc version 5.1.0 (GCC)
-------

Attached:
- code.ii


Thank you for all your work.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]