[PATCH v2 3/8] selftests/mm: pass down full CC and CFLAGS to check_config.sh

Kevin Brodsky
2026-01-07T16:49:01Z

check_config.sh checks that liburing is available by running the
compiler provided as its first argument. This makes two assumptions:

1. CC consists of only one word
2. No extra flag is required

Unfortunately, there are many situations where these assumptions
don't hold. For instance:

- When using Clang, CC consists of multiple words
- When cross-compiling, extra flags may be required to allow the
compiler to find headers

Remove these assumptions by passing down CC and CFLAGS as-is from
the Makefile, so that the same command line is used as when actually
building the tests.

Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
---
tools/testing/selftests/mm/Makefile | 2 +-
tools/testing/selftests/mm/check_config.sh | 3 +--
2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index 4e5c8a330a0c..de4afc34e3b1 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -230,7 +230,7 @@ $(OUTPUT)/migration: LDLIBS += -lnuma
$(OUTPUT)/rmap: LDLIBS += -lnuma

local_config.mk local_config.h: check_config.sh
- /bin/sh ./check_config.sh $(CC)
+ CC="$(CC)" CFLAGS="$(CFLAGS)" ./check_config.sh

EXTRA_CLEAN += local_config.mk local_config.h

diff --git a/tools/testing/selftests/mm/check_config.sh b/tools/testing/selftests/mm/check_config.sh
index 3954f4746161..b84c82bbf875 100755
--- a/tools/testing/selftests/mm/check_config.sh
+++ b/tools/testing/selftests/mm/check_config.sh
@@ -16,8 +16,7 @@ echo "#include <sys/types.h>" > $tmpfile_c
echo "#include <liburing.h>" >> $tmpfile_c
echo "int func(void) { return 0; }" >> $tmpfile_c

-CC=${1:?"Usage: $0 <compiler> # example compiler: gcc"}
-$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1
+$CC $CFLAGS -c $tmpfile_c -o $tmpfile_o

if [ -f $tmpfile_o ]; then
echo "#define LOCAL_CONFIG_HAVE_LIBURING 1" > $OUTPUT_H_FILE
--
2.51.2