[Bug target/71261] New: Trunk GCC hangs on knl and broadwell targets

["anton.mitrokhin at phystech dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71261

            Bug ID: 71261
           Summary: Trunk GCC hangs on knl and broadwell targets
           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 38555
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38555&action=edit
Reproducer

Trunk GCC hangs on knl and broadwell targets

hang.cpp attached

Run:
> g++ -std=c++11 -O3 -march=broadwell -c -o out.o hang.cpp

or

> g++ -std=c++11 -O3 -march=knl -c -o out.o hang.cpp


> 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/)