Kbuild provides scripts/Makefile.host to build host programs used for building the kernel. Unfortunately, there are two exceptions that opt out of Kbuild. The build system under tools/ is a cheesy replica, and is always a disaster. I was recently poked about a problem in the tools build issue, which I do not maintain (and nobody maintains). [1] Without a comment, somebody might believe this is the right location because that is where objtool lives, even when a more robust Kbuild syntax satisfies their needs. [2] [1]: https://lore.kernel.org/linux-kbuild/ZnIYWBgrJ-IJtqK8@xxxxxxxxxx/T/#m8ece130dd0e23c6f2395ed89070161948dee8457 [2]: https://lore.kernel.org/all/20240618200501.GA1611012@xxxxxxxxxx/ Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> --- Makefile | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Makefile b/Makefile index 471f2df86422..ba070596ad4e 100644 --- a/Makefile +++ b/Makefile @@ -1331,6 +1331,11 @@ prepare: tools/bpf/resolve_btfids endif endif +# README +# The tools build system is not a part of Kbuild. Before adding yet another +# tools/* here, please consider if the standard "hostprogs" syntax satisfies +# your needs. + PHONY += resolve_btfids_clean resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids -- 2.43.0
