When cross compiling a MIPS kernel on a BSD based HOSTCC leads to errors like SYNC include/config/auto.conf.cmd - due to: .config egrep: empty (sub)expression UPD include/config/kernel.release HOSTCC scripts/dtc/dtc.o - due to target missing It turns out that egrep uses this egrep pattern: (|MINOR_|PATCHLEVEL_) This is not valid syntax or gives undefined results according to POSIX 9.5.3 ERE Grammar https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html It seems to be silently accepted by the Linux egrep implementation while a BSD host complains. Such patterns can be replaced by a transformation like "(|p1|p2)" -> "(p1|p2)?" Fixes: 48c35b2d245f ("[MIPS] There is no __GNUC_MAJOR__") Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> --- arch/mips/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/Makefile b/arch/mips/Makefile index 258234c35a096..674f68d16a73f 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -321,7 +321,7 @@ KBUILD_LDFLAGS += -m $(ld-emul) ifdef CONFIG_MIPS CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \ - egrep -vw '__GNUC_(|MINOR_|PATCHLEVEL_)_' | \ + egrep -vw '__GNUC_(MINOR_|PATCHLEVEL_)?_' | \ sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g') endif -- 2.31.1
