[PATCH v12 0/3] kbuild: distributed build support for Clang ThinLTO

[xur]

From: Rong Xu <xur@xxxxxxxxxx>

ChangeLog:

V12: Fixed an build error reported by Nathan Chancellor:
     Reverted to v10 shell script based approach to get saved_c_flags.
V11: Integrated feedback from Sashiko (Nathan Chancellor):
     (1) Included modkern_cflags within the saved _c_flags.
     (2) Replaced the shell command with $(saved_c_flags_$(<)).
     (3) Refined the file matching for ar_vmlinux.a.
V10: Fixed a minor build error in v9 and added comments.
V9:  Fixed a minor build error.
V8:  Disabled -always-rename-promoted-locals=false for the distrubute
     mode, based on Yonghong and Nathan's comments.
V7: (1) Resolved a conflict by rebasing to kbuild/kbuild-next-unstable.
    (2) Separated the '--thin' to 'T' change into its own patch to
        preserve Masahiro's original version.
V6: Change '--thin' back to 'T' in Makefile.vmlinux_a to fix
    reported the build error from old ar.
V5: Handle single quote escaping in echo _c_flags to fix
    Piotr Gorski's reported error.
V4: This is based on the reimplementation provided by Masahiro Yamada
on May 26. The difference is that this version now saves the compiler
flags (_c_flags) from the Front-End (FE) compilation and re-uses them
for the subsequent Back-End (BE) compilation.

Rong Xu (3):
  kbuild: move vmlinux.a build rule to scripts/Makefile.vmlinux_a
  kbuild: change --thin back to 'T' in $(AR)
  kbuild: distributed build support for Clang ThinLTO

 .gitignore                 |  2 +
 Makefile                   | 30 +++++++-------
 arch/Kconfig               | 19 +++++++++
 scripts/Makefile.lib       |  8 ++++
 scripts/Makefile.thinlto   | 40 ++++++++++++++++++
 scripts/Makefile.vmlinux_a | 83 ++++++++++++++++++++++++++++++++++++++
 scripts/mod/modpost.c      | 15 +++++--
 7 files changed, 180 insertions(+), 17 deletions(-)
 create mode 100644 scripts/Makefile.thinlto
 create mode 100644 scripts/Makefile.vmlinux_a


base-commit: 2c31897a17e55a6da529b4e797e98c6febc60fd2
-- 
2.54.0.823.g6e5bcc1fc9-goog