Re: [PATCH] Makefile: check for cppcheck's --check-level option in cppcheck target

On Wed, 28 Feb 2024 08:24:49 +1100
David Gibson <david(a)gibson.dropbear.id.au> wrote:

...
  On Tue, Feb 27, 2024 at 05:29:47PM +0100, Stefano
Brivio wrote:
  Don't run cppcheck to find out if the
--check-level=exhaustive option
 is available, unless we're actually going to run cppcheck later.
 
 To avoid this, move this check under the cppcheck target, and
 implement it in shell script instead of using Makefile directives,
 because we can't easily implement conditionals in recipes.
 
 Reported-by: Rahil Bhimjiani <me(a)rahil.website>
 Link: https://bugs.gentoo.org/920795
 Fixes: 8640d62af719 ("cppcheck: Use "exhaustive" level checking when
available")
 Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com>
 ---
  Makefile | 10 +++++-----
  1 file changed, 5 insertions(+), 5 deletions(-)
 
 diff --git a/Makefile b/Makefile
 index af4fa87..75d0bf3 100644
 --- a/Makefile
 +++ b/Makefile
 @@ -287,17 +287,17 @@ clang-tidy: $(SRCS) $(HEADERS)
  	-config='{CheckOptions: [{key:
bugprone-suspicious-string-compare.WarnOnImplicitComparison, value:
"false"}]}' \
  	--warnings-as-errors=* $(SRCS) -- $(filter-out -pie,$(FLAGS) $(CFLAGS) $(CPPFLAGS))
-DCLANG_TIDY_58992
  
 -CPPCHECK_EXHAUSTIVE :=
 -ifeq ($(shell cppcheck --check-level=exhaustive /dev/null > /dev/null 2>&1;
echo $$?),0)
 -	CPPCHECK_EXHAUSTIVE += --check-level=exhaustive
 -endif
 -
  SYSTEM_INCLUDES := /usr/include $(wildcard /usr/include/$(TARGET))
  ifeq ($(shell $(CC) -v 2>&1 | grep -c "gcc version"),1)
  VER := $(shell $(CC) -dumpversion)
  SYSTEM_INCLUDES += /usr/lib/gcc/$(TARGET)/$(VER)/include
  endif
  cppcheck: $(SRCS) $(HEADERS)
 +	if cppcheck --check-level=exhaustive /dev/null > /dev/null 2>&1; then \
 +		CPPCHECK_EXHAUSTIVE="--check-level=exhaustive";		\
 +	else								\
 +		CPPCHECK_EXHAUSTIVE=;					\
 +	fi;								\
  	cppcheck --std=c11 --error-exitcode=1 --enable=all --force	\
  	--inconclusive --library=posix --quiet				\
  	$(CPPCHECK_EXHAUSTIVE)						\   
 
 IIUC, this is essentially moving CPPCHECK_EXHAUSTIVE from a make
 variable to a shell variable in the shell that make invokes.  Which is
 fine, but I believe $(CPPCHECK_EXHAUSTIVE) will only expand to a make
 variable.  To get the shell variable you'll need
 $${CPPCHECK_EXHAUSTIVE}.  I suspect as written, this will always
 expand empty. 
Oops, you're right, I had only tested the negative case. Fixed in v2.

-- 
Stefano