In options like -march=, it may be only the sub-option which is unrecognized by the compiler. In such an event the error message often splits option and argument, typically saying something like "bad value '<argument>' for '<option>'. Extend the grep invocation accordingly, also accounting for Clang to not mention e.g. -march at all when an incorrect argument was given for it.
To keep things halfway readable, re-wrap and re-indent the entire construct. Signed-off-by: Jan Beulich <[email protected]> --- In principle -e "$$pat" could now be omitted from the grep invocation, since if that matches, both $$opt and $$arg will, too. But I thought I'd leave it for completeness. --- v2: Further relax grep patterns for clang, which doesn't mention -march when complaining about an invalid argument to it. --- a/Config.mk +++ b/Config.mk @@ -90,9 +90,14 @@ PYTHON_PREFIX_ARG ?= --prefix="$(prefix) # of which would indicate an "unrecognized command-line option" warning/error. # # Usage: cflags-y += $(call cc-option,$(CC),-march=winchip-c6,-march=i586) -cc-option = $(shell if test -z "`echo 'void*p=1;' | \ - $(1) $(2) -c -o /dev/null -x c - 2>&1 | grep -- $(2:-Wa$(comma)%=%) -`"; \ - then echo "$(2)"; else echo "$(3)"; fi ;) +cc-option = $(shell pat='$(2:-Wa$(comma)%=%)'; \ + opt="$${pat%%=*}" arg="$${pat\#*=}"; \ + if test -z "`echo 'void*p=1;' | \ + $(1) $(2) -c -o /dev/null -x c - 2>&1 | \ + grep -e "$$pat" -e "$$opt" -e "$$arg" -`"; \ + then echo "$(2)"; \ + else echo "$(3)"; \ + fi;) # cc-option-add: Add an option to compilation flags, but only if supported. # Usage: $(call cc-option-add CFLAGS,CC,-march=winchip-c6)
