Re: [PATCH 0/3] fixes for CLANG35 on ARM

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

Make sense. So, CLANG35 tool chain can also be used by CLANG 3.5 and above version compiler, like GCC49?

> -----Original Message-----
> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ard Biesheuvel
> Sent: Wednesday, December 12, 2018 10:03 PM
> To: Gao, Liming <liming.gao@intel.com>
> Cc: Kinney, Michael D <michael.d.kinney@intel.com>; edk2-devel@lists.01.org; Laszlo Ersek <lersek@redhat.com>
> Subject: Re: [edk2] [PATCH 0/3] fixes for CLANG35 on ARM
> 
> On Wed, 12 Dec 2018 at 15:01, Gao, Liming <liming.gao@intel.com> wrote:
> >
> > Ard:
> >   I have no comments on this patch. So, CLANG38 has no issue. If so, could you recommend use CLANG38?
> >
> 
> Yes, the latest is always preferred. However, since CLANG38 enables
> LTO, you need the LLVMgold plugin, which is not shipped for all
> versions of Clang by the distros. So it is good to keep CLANG35 as a
> fallback.
> 
> > > -----Original Message-----
> > > From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> > > Sent: Wednesday, December 12, 2018 6:33 PM
> > > To: edk2-devel@lists.01.org
> > > Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>; Kinney, Michael D <michael.d.kinney@intel.com>; Gao, Liming
> > > <liming.gao@intel.com>; Feng, Bob C <bob.c.feng@intel.com>; Leif Lindholm <leif.lindholm@linaro.org>; Laszlo Ersek
> > > <lersek@redhat.com>
> > > Subject: [PATCH 0/3] fixes for CLANG35 on ARM
> > >
> > > Building with Clang 3.5 for ARM may result in build breakage, due to the
> > > fact that it may emit non-adjacent movw/movt instructions pairs which
> > > cannot be relocated in PE/COFF. We pass -mno-movt in some places to
> > > work around a related issue in the relocatable PrePi in ArmVirtPkg, but
> > > we need to disable movw/movt entirely to really address this issue.
> > >
> > > So first, fix some breakage that results from building with -mlong-calls
> > > in the optimized BaseMemoryLib code (#1)
> > >
> > > Patch #2 switches to -mkernel, which disables movw/movt generation (and
> > > enabled -mlong-calls as a side effect)
> > >
> > > Patch #3 removes the now redundant, and incompatible command line
> > > overrides for the relocatable PrePi.
> > >
> > > Cc: Michael D Kinney <michael.d.kinney@intel.com>
> > > Cc: Liming Gao <liming.gao@intel.com>
> > > Cc: Bob Feng <bob.c.feng@intel.com>
> > > Cc: Leif Lindholm <leif.lindholm@linaro.org>
> > > Cc: Laszlo Ersek <lersek@redhat.com>
> > >
> > > Ard Biesheuvel (3):
> > >   MdePkg/BaseMemoryLibOptDxe ARM: add missing function annotations
> > >   BaseTools/tools_def ARM CLANG35: work around -mno-movt option name
> > >     change
> > >   ArmVirtPkg/PrePi ARM CLANG35: drop incompatible command line option
> > >
> > >  ArmVirtPkg/ArmVirtQemuKernel.dsc                     | 5 -----
> > >  ArmVirtPkg/ArmVirtXen.dsc                            | 5 -----
> > >  BaseTools/Conf/tools_def.template                    | 2 +-
> > >  MdePkg/Library/BaseMemoryLibOptDxe/Arm/CompareGuid.S | 1 +
> > >  MdePkg/Library/BaseMemoryLibOptDxe/Arm/CompareMem.S  | 1 +
> > >  MdePkg/Library/BaseMemoryLibOptDxe/Arm/CopyMem.S     | 1 +
> > >  MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S      | 5 +++++
> > >  7 files changed, 9 insertions(+), 11 deletions(-)
> > >
> > > --
> > > 2.19.2
> >
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