Re: [edk2-devel] [Patch] BaseTools tools_def.template: Add back -fno-pie option in GCC49 tool chain

["Liming Gao" <liming.gao@intel.com>]

Mike:
  GCC IA32 arch requires -fno-pie option. You can check the commit c25d3905523ae4961bb039b1aba597983f7e3e4e "BaseTools/tools_def IA32: disable PIE code generation explicitly". 
  GCC X64 arch requires -fpie option. You can check the commit f49513f666ed25d24bdf3a02a1fdb5d18ae081c0 " BaseTools/tools_def: switch GCC/X64 to the PIE small model".

  This patch is to add back -fno-pie option for GCC IA32 arch. GCC X64 arch still requires -fpie option. So, your change is still required for X64 host.

Thanks
Liming
> -----Original Message-----
> From: Kinney, Michael D <michael.d.kinney@intel.com>
> Sent: Wednesday, February 5, 2020 12:22 AM
> To: devel@edk2.groups.io; Gao, Liming <liming.gao@intel.com>; Laszlo Ersek <lersek@redhat.com>; Kinney, Michael D
> <michael.d.kinney@intel.com>
> Cc: Feng, Bob C <bob.c.feng@intel.com>; Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Subject: RE: [edk2-devel] [Patch] BaseTools tools_def.template: Add back -fno-pie option in GCC49 tool chain
> 
> Liming,
> 
> Can you please provide a few more details on the failure.
> 
> For the UnitTestFrameworkPkg patch set, I had to add the
> following to get host based unit test applications to build
> and run.  I was seeing link failures between FW libs and
> host libs when building the POSIX host application.
> 
> [BuildOptions]
>   GCC:*_*_*_CC_FLAGS = -fno-pie
> 
> I think with the proposed change below, I could remove
> this. Do you agree?
> 
> Thanks,
> 
> Mike
> 
> 
> > -----Original Message-----
> > From: devel@edk2.groups.io <devel@edk2.groups.io> On
> > Behalf Of Liming Gao
> > Sent: Tuesday, February 4, 2020 4:52 AM
> > To: Laszlo Ersek <lersek@redhat.com>;
> > devel@edk2.groups.io
> > Cc: Feng, Bob C <bob.c.feng@intel.com>; Ard Biesheuvel
> > <ard.biesheuvel@linaro.org>; Gao, Liming
> > <liming.gao@intel.com>
> > Subject: Re: [edk2-devel] [Patch] BaseTools
> > tools_def.template: Add back -fno-pie option in GCC49
> > tool chain
> >
> > Laszlo:
> >
> > > -----Original Message-----
> > > From: Laszlo Ersek <lersek@redhat.com>
> > > Sent: Tuesday, February 4, 2020 8:02 PM
> > > To: devel@edk2.groups.io; Gao, Liming
> > <liming.gao@intel.com>
> > > Cc: Feng, Bob C <bob.c.feng@intel.com>; Ard
> > Biesheuvel <ard.biesheuvel@linaro.org>
> > > Subject: Re: [edk2-devel] [Patch] BaseTools
> > tools_def.template: Add back -fno-pie option in GCC49
> > tool chain
> > >
> > > (+Ard)
> > >
> > > On 02/04/20 05:54, Liming Gao wrote:
> > > > BZ:
> > https://bugzilla.tianocore.org/show_bug.cgi?id=2502
> > > > This option is required to make GCC49 tool chain
> > work with the high
> > > > version GCC compiler.
> > > >
> > > > Cc: Bob Feng <bob.c.feng@intel.com>
> > > > Signed-off-by: Liming Gao <liming.gao@intel.com>
> > > > ---
> > > >  BaseTools/Conf/tools_def.template | 4 ++--
> > > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/BaseTools/Conf/tools_def.template
> > b/BaseTools/Conf/tools_def.template
> > > > index feee2bbf16..d02424ae44 100755
> > > > --- a/BaseTools/Conf/tools_def.template
> > > > +++ b/BaseTools/Conf/tools_def.template
> > > > @@ -1974,7 +1974,7 @@ DEFINE
> > GCC48_ARM_ASLDLINK_FLAGS      =
> > DEF(GCC_ARM_ASLDLINK_FLAGS) -Wl,--oformat
> > > >  DEFINE GCC48_AARCH64_ASLDLINK_FLAGS  =
> > DEF(GCC_AARCH64_ASLDLINK_FLAGS)
> > > >  DEFINE GCC48_ASLCC_FLAGS             =
> > DEF(GCC_ASLCC_FLAGS)
> > > >
> > > > -DEFINE GCC49_IA32_CC_FLAGS           =
> > DEF(GCC48_IA32_CC_FLAGS)
> > > > +DEFINE GCC49_IA32_CC_FLAGS           =
> > DEF(GCC48_IA32_CC_FLAGS) -fno-pic -fno-pie
> > > >  DEFINE GCC49_X64_CC_FLAGS            =
> > DEF(GCC48_X64_CC_FLAGS)
> > > >  DEFINE GCC49_IA32_X64_DLINK_COMMON   = -nostdlib -
> > Wl,-n,-q,--gc-sections -z common-page-size=0x40
> > > >  DEFINE GCC49_IA32_X64_ASLDLINK_FLAGS =
> > DEF(GCC49_IA32_X64_DLINK_COMMON) -Wl,--
> > defsym=PECOFF_HEADER_SIZE=0
> > > DEF(GCC_DLINK2_FLAGS_COMMON) -Wl,--
> > entry,ReferenceAcpiTable -u ReferenceAcpiTable
> > > > @@ -1997,7 +1997,7 @@ DEFINE
> > GCC49_ARM_ASLDLINK_FLAGS      =
> > DEF(GCC48_ARM_ASLDLINK_FLAGS)
> > > >  DEFINE GCC49_AARCH64_ASLDLINK_FLAGS  =
> > DEF(GCC48_AARCH64_ASLDLINK_FLAGS)
> > > >  DEFINE GCC49_ASLCC_FLAGS             =
> > DEF(GCC48_ASLCC_FLAGS)
> > > >
> > > > -DEFINE GCC5_IA32_CC_FLAGS            =
> > DEF(GCC49_IA32_CC_FLAGS) -fno-pic -fno-pie
> > > > +DEFINE GCC5_IA32_CC_FLAGS            =
> > DEF(GCC49_IA32_CC_FLAGS)
> > > >  DEFINE GCC5_X64_CC_FLAGS             =
> > DEF(GCC49_X64_CC_FLAGS)
> > > >  DEFINE GCC5_IA32_X64_DLINK_COMMON    =
> > DEF(GCC49_IA32_X64_DLINK_COMMON)
> > > >  DEFINE GCC5_IA32_X64_ASLDLINK_FLAGS  =
> > DEF(GCC49_IA32_X64_ASLDLINK_FLAGS)
> > > >
> > >
> > > - What has changed relative to commit 11d0cd23dd1b
> > ("BaseTools/tools_def
> > > IA32: drop -no-pie linker option for GCC49", 2018-06-
> > 18)?
> > >
> > > - Also, if we are reverting one half of 11d0cd23dd1b
> > (the compiler
> > > flags), shouldn't we then revert the other half too
> > (the linker flags)?
> >
> > Yes. Half change is revert. CC_FLAGS is added back.
> > DLINK flag is not,
> > because GCC4.9 doesn't know the link option -no-pie.
> > But, GCC 4.9 accepts the CC option -fno-pie.
> > I verify this change. CC flags -fno-pie can resolve the
> > build failure with GCC7.4. I also see -fno-pie option
> > Is in GCC ARM and AARCH64 arch. So, I think this change
> > is enough.
> >
> > >
> > > - The commit message says, "work with the high
> > version GCC compiler".
> > > What does that mean? If it is 4.9.x, with x>2, then I
> > agree the patch is
> > > justified (because commit 11d0cd23dd1b was apparently
> > made for 4.9.2).
> > > But if the phrase stands for gcc8 or so (just an
> > example), then I don't
> > > think the patch is a good idea; users of gcc8 can
> > just specify the GCC5
> > > toolchain.
> > >
> > > Ah, indeed, I need only look at TianoCore#2502:
> > >
> > > "GCC49 tool chain meets with the build failure when
> > GCC7.4 compiler".
> > >
> > > So I think this approach is wrong. Unless there is a
> > new gcc-4.9.x
> > > release, i.e., after gcc-4.9.2, I think we still need
> > commit
> > > 11d0cd23dd1b in place. And, please use GCC5 for gcc-
> > 7.4 -- is there a
> > > problem with that?
> >
> > By design, GCC49 can work with the high version GCC
> > compiler like GCC5.
> > GCC49 is the tool chain without LTO enable. GCC5 is the
> > tool chain with LTO.
> > So, they are for two different GCC setting. They should
> > both support
> > high version GCC compiler. GCC49 supported GCC compiler
> > version is from GCC 4.9.
> > GCC5 supported GCC compiler version is from GCC 5.0. I
> > know GCC49 or GCC5 tool chain
> > name brings a little confuse. I will add more detail
> > info in tools_def.txt for them.
> >
> > Thanks
> > Liming
> > >
> > > Thanks
> > > Laszlo
> >
> >
> >