https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71259
Bug ID: 71259
Summary: GCC trunk emits wrong code
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: anton.mitrokhin at phystech dot edu
Target Milestone: ---
Created attachment 38552
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38552&action=edit
Reproducer
GCC trunk generates wrong code with -O3/Ofast on 'ivybridge' target (not sure
about other targets though)
crash.cpp is attached.
Run:
> g++ -static-libgcc -static-libstdc++ -std=c++11 -O2 -march=ivybridge -o out0
> crash.cpp
> g++ -static-libgcc -static-libstdc++ -std=c++11 -O3 -march=ivybridge -o out1
> crash.cpp
Output:
> ./out0: -5105075050047261684
> ./out1: -5105075050047261682
> gcc -v:
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/export/users/amitrokh/gcc_trunk/bin/../libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /export/users/gnutester/stability/svn/trunk/configure
--with-arch=corei7 --with-cpu=corei7 --enable-clocale=gnu --with-system-zlib
--enable-shared --with-demangler-in-ld --enable-cloog-backend=isl
--with-fpmath=sse --with-pkgversion=Revision=236614/svn-rev:236614/
--prefix=/export/users/gnutester/stability/work/trunk/64/install
--enable-languages=c,c++,fortran,java,lto
Thread model: posix
gcc version 7.0.0 20160523 (experimental) (Revision=236614/svn-rev:236614/)
