From: Paul Menzel pmenzel@molgen.mpg.de
[ 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 --- 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 b9e6c3648be1..98b9fd0354dd 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 $(OPTFLAGS) @@ -47,7 +49,7 @@ else ifeq ($(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