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Date:   Thu,  8 Jul 2021 16:25:20 -0700
Message-Id: <20210708232522.3118208-1-ndesaulniers@google.com>
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Subject: [PATCH v2 0/2] infer CROSS_COMPILE from SRCARCH for LLVM=1 LLVM_IAS=1
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Miguel Ojeda <ojeda@kernel.org>, Fangrui Song <maskray@google.com>,
        Michal Marek <michal.lkml@markovi.net>,
        Arnd Bergmann <arnd@kernel.org>, linux-kernel@vger.kernel.org,
        linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Christoph Hellwig <hch@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Nick Desaulniers <ndesaulniers@google.com>
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Precedence: bulk

We get constant feedback that the command line invocation of make is too
long. CROSS_COMPILE is helpful when a toolchain has a prefix of the
target triple, or is an absolute path outside of $PATH, but it's mostly
redundant for a given ARCH.

Instead, let's infer it from SRCARCH, and move some flag handling into a
new file included from the top level Makefile.

Changes v1 -> v2:
* patch 1/2 untouched.
* Fix typos in commit message as per Geert and Masahiro.
* Use SRCARCH instead of ARCH, simplifying x86 handling, as per
  Masahiro. Add his sugguested by tag.
* change commit oneline from 'drop' to 'infer.'
* Add detail about explicit host --target and relationship of ARCH to
  SRCARCH, as per Masahiro.

Nick Desaulniers (2):
  Makefile: move initial clang flag handling into scripts/Makefile.clang
  Makefile: infer CROSS_COMPILE from SRCARCH for LLVM=1 LLVM_IAS=1

 Documentation/kbuild/llvm.rst |  5 ++++
 MAINTAINERS                   |  1 +
 Makefile                      | 15 +-----------
 scripts/Makefile.clang        | 44 +++++++++++++++++++++++++++++++++++
 4 files changed, 51 insertions(+), 14 deletions(-)
 create mode 100644 scripts/Makefile.clang


base-commit: a0e781a2a35a8dd4e6a38571998d59c6b0e32cd8
-- 
2.32.0.93.g670b81a890-goog