On Thu, Dec 04, 2025 at 09:40:54AM -0800, Jakub Kicinski wrote: > On Thu, 4 Dec 2025 08:17:20 -0800 Guenter Roeck wrote: > > -CFLAGS += $(KHDR_INCLUDES) -Wall -Wflex-array-member-not-at-end > > +CFLAGS += $(KHDR_INCLUDES) -Wall $(call > > cc-option,-Wflex-array-member-not-at-end) > > Hm, the Claude code review we have hooked up to patchwork says: > > Is cc-option available in the selftest build environment? Looking at > tools/testing/selftests/lib.mk (included at line 14), it doesn't include > scripts/Makefile.compiler where cc-option is defined. When cc-option is > undefined, $(call cc-option,...) expands to an empty string, which means > the -Wflex-array-member-not-at-end flag won't be added even on compilers > that support it. > > This defeats the purpose of commit 1838731f1072c which added the warning > flag to catch flexible array issues. > > For comparison, tools/testing/selftests/nolibc/Makefile explicitly > includes scripts/Makefile.compiler before using cc-option. > > Testing it: > > $ make -C tools/testing/selftests/ TARGETS=net/af_unix Q= V=1 > make: Entering directory '/home/kicinski/devel/linux/tools/testing/selftests' > make[1]: Entering directory > '/home/kicinski/devel/linux/tools/testing/selftests/net/af_unix' > gcc -isystem /home/kicinski/devel/linux/usr/include -Wall -D_GNU_SOURCE= > diag_uid.c -o > /home/kicinski/devel/linux/tools/testing/selftests/net/af_unix/diag_uid > > looks like the flag just disappears. Even tho: > > gcc version 15.2.1
Oops :). I didn't expect that, sorry. Thanks for finding! ... and I guess it's time to set up AI in my environment. Guenter
