From 4719c9264131b88fef209dc3342c23d3ac5356bd Mon Sep 17 00:00:00 2001 From: Konstantin Khorenko Date: Thu, 1 Oct 2026 18:57:11 +0200 Subject: [PATCH] kbuild: use $(CFLAGS_GCOV) in the prefer-atomic try-run test Patch series "kbuild: GCOV cleanups following the prefer-atomic fix". Two cleanups Peter Oberparleiter suggested while reviewing commit 56cb9b7d96b2 ("gcov: use atomic counter updates to fix concurrent access crashes"): https://lore.kernel.org/e1b6e768-51af-468b-a729-0ed3fceef2f1@linux.ibm.com Patch 1 makes the prefer-atomic try-run test reuse $(CFLAGS_GCOV) instead of spelling the flags out again, so the test compiles with the exact GCOV flags, -fno-tree-loop-im included. Patch 2 moves the CFLAGS_GCOV block into scripts/Makefile.gcov, included via include-$(CONFIG_GCOV_KERNEL) like the other instrumentation makefiles. The try-run also stops running on builds without GCOV. This patch (of 2): Reference $(CFLAGS_GCOV) in the try-run test introduced by commit 56cb9b7d96b2 ("gcov: use atomic counter updates to fix concurrent access crashes"), otherwise it can miss potential future changes in the list of flags used for GCOV profiling like it misses -fno-tree-loop-im at the moment. The outcome of the test is unchanged: -fno-tree-loop-im does not affect the undefined symbols the test compares. Link: https://lore.kernel.org/20261001-b4-prep-gcov-v1-0-794792e06f24@virtuozzo.com Link: https://lore.kernel.org/20261001-b4-prep-gcov-v1-1-794792e06f24@virtuozzo.com Signed-off-by: Konstantin Khorenko Signed-off-by: Andrew Morton Suggested-by: Peter Oberparleiter Cc: Nathan Chancellor Cc: Nicolas Schier Cc: Masahiro Yamada Cc: Arnd Bergmann Cc: Mikhail Zaslonko --- Makefile | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/Makefile b/Makefile index 6b8b812f23b9..3b69b973f759 100644 --- a/Makefile +++ b/Makefile @@ -1184,11 +1184,11 @@ CFLAGS_GCOV += -fno-tree-loop-im # undefined symbols (e.g. libatomic calls that the kernel cannot link). CFLAGS_GCOV += $(call try-run,\ echo 'long long x; void f(void){x++;}' | \ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w -fprofile-arcs \ - -ftest-coverage -x c - -c -o "$$TMP.base" && \ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ + -x c - -c -o "$$TMP.base" && \ echo 'long long x; void f(void){x++;}' | \ - $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w -fprofile-arcs \ - -ftest-coverage -fprofile-update=prefer-atomic \ + $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -w $(CFLAGS_GCOV) \ + -fprofile-update=prefer-atomic \ -x c - -c -o "$$TMP" && \ $(NM) "$$TMP.base" | grep ' U ' > "$$TMP.ubase" || true ; \ $(NM) "$$TMP" | grep ' U ' > "$$TMP.utest" || true ; \