On Thu, Aug 08, 2019 at 03:42:32PM -0700, 'Nick Desaulniers' via Clang Built Linux wrote: > On Thu, Aug 8, 2019 at 2:07 PM Guillaume Tucker > <guillaume.tucker@xxxxxxxxxxxxx> wrote: > > > > Only use gcc/g++ for HOSTCC, HOSTCXX and CC by default if they are not > > already defined in the environment. This fixes cases such as building > > host tools with clang without having gcc installed. > > > > The issue was initially hit when running merge_config.sh with clang > > only as it failed to build "HOSTCC scripts/basic/fixdep". > > Thanks for the patch. I don't quite follow the exact error. > > When building with Clang, I usually do: > > $ make CC=clang HOSTCC=clang ... > > are you trying to fix the case where you do: > > $ make CC=clang ... > <no HOSTCC set> > when GCC is not installed? Because if so, I think it would be easier > to just specify HOSTCC=clang, but maybe I'm misunderstanding the > issue? As I understand it, $ make CC=clang HOSTCC=clang works fine. What doesn't currently work is: $ export CC=clang $ export HOSTCC=clang $ make This is problematic because there is no way for CC, HOSTCC, and HOSTCXX to be passed to make within scripts/kconfig/merge_config.sh. A quick test before and after the patch: $ ( export HOSTCC=clang; make -j$(nproc) O=out defconfig V=1 ) ... gcc -Wp,-MD,scripts/kconfig/.conf.o.d -Wall -Wmissing-prototypes... gcc -Wp,-MD,scripts/kconfig/.confdata.o.d -Wall -Wmissing-prototypes... ... $ ( export HOSTCC=clang; make -j$(nproc) O=out defconfig V=1 ) ... clang -Wp,-MD,scripts/kconfig/.conf.o.d -Wall -Wmissing-prototypes -Wstrict-prototypes... clang -Wp,-MD,scripts/kconfig/.confdata.o.d -Wall -Wmissing-prototypes -Wstrict-prototypes... ... Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> I wonder if all variable should be converted to that scheme or just the ones that are needed in this instance. I also wonder if this will cause any issues with people who define these variables in their environment already; if so, maybe merge_config.sh should be updated to support passing CC, HOSTCC, and HOSTCXX to make. Cheers, Nathan
