kbuild: install-extmod-build: Properly fix CC expansion when ccache is used

Currently, when cross-compiling and ccache is used, the expanding of CC
turns out to be without any quotes, leading to the following error:

make[4]: *** No rule to make target 'aarch64-linux-gnu-gcc'.  Stop.
make[3]: *** [Makefile:2164: run-command] Error 2

And it makes sense, because after expansion it ends up like this:

make run-command KBUILD_RUN_COMMAND=+$(MAKE) \
HOSTCC=ccache aarch64-linux-gnu-gcc VPATH= srcroot=. $(build)= ...

So add another set of double quotes to surround whatever CC expands to
to make sure the aarch64-linux-gnu-gcc isn't expanded to something that
looks like an entirely separate target.

Fixes: 140332b6ed72 ("kbuild: fix linux-headers package build when $(CC) cannot link userspace")
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20251111-kbuild-install-extmod-build-fix-cc-expand-third-try-v2-1-15ba1b37e71a@linaro.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

diff --git a/scripts/package/install-extmod-build b/scripts/package/install-extmod-build
index 054fdf45cc37a8717444b8094daf3e1150a8ccf5..2576cf7902dbbfcd82ea690aac1b2a246b3a6a30 100755 (executable)
--- a/scripts/package/install-extmod-build
+++ b/scripts/package/install-extmod-build
@@ -63,7 +63,7 @@ if [ "${CC}" != "${HOSTCC}" ]; then
        # Clear VPATH and srcroot because the source files reside in the output
        # directory.
        # shellcheck disable=SC2016 # $(MAKE) and $(build) will be expanded by Make
-       "${MAKE}" run-command KBUILD_RUN_COMMAND='+$(MAKE) HOSTCC='"${CC}"' VPATH= srcroot=. $(build)='"$(realpath --relative-to=. "${destdir}")"/scripts
+       "${MAKE}" run-command KBUILD_RUN_COMMAND='+$(MAKE) HOSTCC="'"${CC}"'" VPATH= srcroot=. $(build)='"$(realpath --relative-to=. "${destdir}")"/scripts
 
        rm -f "${destdir}/scripts/Kbuild"
 fi