linux/Documentation/kbuild
Elliot Berman 3172c95582 FROMLIST: kbuild: Add environment variables for userprogs flags
Allow additional arguments be passed to userprogs compilation.
Reproducible clang builds need to provide a sysroot and gcc path to
ensure the same toolchain is used across hosts. KCFLAGS is not currently
used for any user programs compilation, so add new USERCFLAGS and
USERLDFLAGS which serves similar purpose as HOSTCFLAGS/HOSTLDFLAGS.

Clang 13+ might detect GCC installation on hosts which have it installed
to a default location in /. With addition of these environment
variables, you can specify flags such as:

$ make USERCFLAGS=--sysroot=/path/to/sysroot

This can also be used to specify different sysroots such as musl or
bionic which may be installed on the host in paths that the compiler
may not search by default.

Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Bug: 214127735
Link: https://lore.kernel.org/linux-kbuild/20220201213542.2808035-1-quic_eberman@quicinc.com/
Change-Id: I035309a569130774a1212f294973eee2830a6588
(cherry picked from commit df704104322c6bd1b3d40cb7ad109cba7453f3be)
2022-05-10 16:09:36 +00:00
..
gcc-plugins.rst Documentation/Kbuild: Remove references to gcc-plugin.sh 2021-12-14 11:32:46 +01:00
headers_install.rst Kbuild updates for v5.3 2019-07-12 16:03:16 -07:00
index.rst Kbuild updates for v5.7 2020-03-31 16:03:39 -07:00
issues.rst docs: kbuild: fix build with pdf and fix some minor issues 2019-07-15 11:03:04 -03:00
kbuild.rst FROMLIST: kbuild: Add environment variables for userprogs flags 2022-05-10 16:09:36 +00:00
kconfig-language.rst Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
kconfig-macro-language.rst kbuild: doc: fix references to other documents 2020-03-13 10:02:27 +09:00
Kconfig.recursion-issue-01 kbuild: document recursive dependency limitation / resolution 2015-10-08 15:36:16 +02:00
Kconfig.recursion-issue-02 kbuild: Replace HTTP links with HTTPS ones 2020-08-10 01:32:59 +09:00
kconfig.rst kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf 2020-01-07 02:18:39 +09:00
Kconfig.select-break kbuild: document recursive dependency limitation / resolution 2015-10-08 15:36:16 +02:00
llvm.rst kbuild: remove unused OBJSIZE 2020-11-02 11:31:00 +09:00
makefiles.rst FROMLIST: kbuild: Add environment variables for userprogs flags 2022-05-10 16:09:36 +00:00
modules.rst ANDROID: kbuild: Add support for installing out-of-tree kernel headers 2020-08-04 18:19:37 +00:00
reproducible-builds.rst gcc-plugins: fix gcc-plugins directory path in documentation 2020-06-28 12:16:55 +09:00