On Fri, 2017-02-10 at 08:48 +0100, Christophe LEROY wrote: > > Le 10/02/2017 à 06:31, Cyril Bur a écrit : > > A bug in the -02 optimisation of GCC 5.4 6.1 and 6.2 causes > > setup_command_line() to not pass the correct first argument to strcpy > > and therefore not actually copy the command_line. > > > > A workaround patch was proposed: http://patchwork.ozlabs.org/patch/673130/ > > some discussion ensued. > > > > A GCC bug was raised: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71709 > > The bug has been fixed in 7.0 and backported to GCC 5 and GCC 6. > > > > At the time of writing GCC 5.4 is the most recent and is affected. GCC > > 6.3 contains the backported fix, has been tested and appears safe to > > use. > > > > Heavy-lifting-by: Akshay Adiga <akshay.ad...@linux.vnet.ibm.com> > > Signed-off-by: Cyril Bur <cyril...@gmail.com> > > --- > > arch/powerpc/Makefile | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > > > diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile > > index 31286fa7873c..a4b886694391 100644 > > --- a/arch/powerpc/Makefile > > +++ b/arch/powerpc/Makefile > > @@ -414,6 +414,15 @@ checkbin: > > echo -n '*** Please use a different binutils version.' ; \ > > false ; \ > > fi > > + @if test "$(cc-version)" = "0504" \ > > + || test "$(cc-version)" = "0601" \ > > + || test "$(cc-version)" = "0602" ; then \ > > + echo -n '*** GCC-5.4 6.1 6.2 have a bad -O2 optimisation ' ; \ > > + echo 'which will cause lost commandline options (at least).' ; \ > > + echo '*** Please use a different GCC version.' ; \ > > + false ; \ > > + fi > > + > > According to the GCC bug report, this bug applies to powerpc64le > Why force all targets to not use those versions of GCC ? >
True, I'll double check on BE, these days BE does suffer from, "oops I didn't check that". If it is only LE, I'll add another condition. Thanks, Cyril > Christophe