From: Paul Menzel pmenzel@molgen.mpg.de
stable inclusion from stable-v5.10.110 commit 1b69302bfae38beeb6fe7ab600d8ddf6e0326930 bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
[ Upstream commit 633174a7046ec3b4572bec24ef98e6ee89bce14b ]
Buidling raid6test on Ubuntu 21.10 (ppc64le) with GNU Make 4.3 shows the errors below:
$ cd lib/raid6/test/ $ make <stdin>:1:1: error: stray ‘\’ in program <stdin>:1:2: error: stray ‘#’ in program <stdin>:1:11: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ \ before ‘<’ token
[...]
The errors come from the HAS_ALTIVEC test, which fails, and the POWER optimized versions are not built. That’s also reason nobody noticed on the other architectures.
GNU Make 4.3 does not remove the backslash anymore. From the 4.3 release announcment:
- WARNING: Backward-incompatibility! Number signs (#) appearing inside a macro reference or function invocation no longer introduce comments and should not be escaped with backslashes: thus a call such as: foo := $(shell echo '#') is legal. Previously the number sign needed to be escaped, for example: foo := $(shell echo '#') Now this latter will resolve to "#". If you want to write makefiles portable to both versions, assign the number sign to a variable: H := # foo := $(shell echo '$H') This was claimed to be fixed in 3.81, but wasn't, for some reason. To detect this change search for 'nocomment' in the .FEATURES variable.
So, do the same as commit 9564a8cf422d ("Kbuild: fix # escaping in .cmd files for future Make") and commit 929bef467771 ("bpf: Use $(pound) instead of # in Makefiles") and define and use a $(pound) variable.
Reference for the change in make: https://git.savannah.gnu.org/cgit/make.git/commit/?id=c6966b323811c37acedff0...
Cc: Matt Brown matthew.brown.dev@gmail.com Signed-off-by: Paul Menzel pmenzel@molgen.mpg.de Signed-off-by: Song Liu song@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- lib/raid6/test/Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/lib/raid6/test/Makefile b/lib/raid6/test/Makefile index a4c7cd74cff5..4fb7700a741b 100644 --- a/lib/raid6/test/Makefile +++ b/lib/raid6/test/Makefile @@ -4,6 +4,8 @@ # from userspace. #
+pound := # + CC = gcc OPTFLAGS = -O2 # Adjust as desired CFLAGS = -I.. -I ../../../include -g $(OPTFLAGS) @@ -42,7 +44,7 @@ else ifeq ($(HAS_NEON),yes) OBJS += neon.o neon1.o neon2.o neon4.o neon8.o recov_neon.o recov_neon_inner.o CFLAGS += -DCONFIG_KERNEL_MODE_NEON=1 else - HAS_ALTIVEC := $(shell printf '#include <altivec.h>\nvector int a;\n' |\ + HAS_ALTIVEC := $(shell printf '$(pound)include <altivec.h>\nvector int a;\n' |\ gcc -c -x c - >/dev/null && rm ./-.o && echo yes) ifeq ($(HAS_ALTIVEC),yes) CFLAGS += -I../../../arch/powerpc/include