dummy/linux-stable-mirror
1
0
Fork 1
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2025-04-19 20:58:31 +09:00
Code Issues Packages Projects Releases Wiki Activity

kbuild: make all file references relative to source root

Browse Source 
-fmacro-prefix-map only affects __FILE__ and __BASE_FILE__.
Other references, for example in debug information, are not affected.
This makes handling of file references in the compiler outputs harder to
use and creates problems for reproducible builds.

Switch to -ffile-prefix map which affects all references.

Also drop the documentation section advising manual specification of
-fdebug-prefix-map for reproducible builds, as it is not necessary
anymore.

Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lore.kernel.org/lkml/c49cc967294f9a3a4a34f69b6a8727a6d3959ed8.camel@decadent.org.uk/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Thomas Weißschuh 2025-03-15 14:20:14 +01:00 committed by Masahiro Yamada
parent 97282e6d38
commit cacd22ce69
2 changed files with 1 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
Documentation/kbuild/reproducible-builds.rst
View File

@ -46,21 +46,6 @@ The kernel embeds the building user and host names in
`KBUILD_BUILD_USER and KBUILD_BUILD_HOST`_ variables. If you are
building from a git commit, you could use its committer address.
Absolute filenames
------------------
When the kernel is built out-of-tree, debug information may include
absolute filenames for the source files. This must be overridden by
including the ``-fdebug-prefix-map`` option in the `KCFLAGS`_ variable.
Depending on the compiler used, the ``__FILE__`` macro may also expand
to an absolute filename in an out-of-tree build. Kbuild automatically
uses the ``-fmacro-prefix-map`` option to prevent this, if it is
supported.
The Reproducible Builds web site has more information about these
`prefix-map options`_.
Generated files in source packages
----------------------------------
@ -131,7 +116,5 @@ See ``scripts/setlocalversion`` for details.
.. _KBUILD_BUILD_TIMESTAMP: kbuild.html#kbuild-build-timestamp
.. _KBUILD_BUILD_USER and KBUILD_BUILD_HOST: kbuild.html#kbuild-build-user-kbuild-build-host
.. _KCFLAGS: kbuild.html#kcflags
.. _prefix-map options: https://reproducible-builds.org/docs/build-path/
.. _Reproducible Builds project: https://reproducible-builds.org/
.. _SOURCE_DATE_EPOCH: https://reproducible-builds.org/docs/source-date-epoch/

2
Makefile
View File

@ -1067,7 +1067,7 @@ endif
# change __FILE__ to the relative path to the source directory
ifdef building_out_of_srctree
KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
KBUILD_CPPFLAGS += $(call cc-option,-ffile-prefix-map=$(srcroot)/=)
KBUILD_RUSTFLAGS += --remap-path-prefix=$(srcroot)/=
endif