On Fri, Jun 16, 2023 at 08:10:44PM +0200, Peter Oberparleiter wrote: > Not that I know of. Here's how it could be made to work using Makefile > magic alone (as a pure programming exercise :) > > This will expand a directory to a list of all parent directories: > > # expand_parents(a/b/c) = a/b/c a/b a > expand_parents2 = $(if $(subst .,,$(1)),$(call expand_parents,$(1)),) > expand_parents = $(1) $(call expand_parents2,$(patsubst %/,%,$(dir $(1)))) > > This list could then be turned into variable suffixes: > > # flatten_dirs(a/b/c) = a_b_c a_b a > flatten_dirs = $(subst /,_,$(call expand_parents,$(1))) > > And finally the resulting list of suffixed variables could be evaluated: > > # eval_vars(X_,a/b/c) = $(X_a_b_c) $(X_a_b) $(X_a) > eval_vars = $(foreach var,$(call flatten_dirs,$(2)),$($(1)$(var))) > > So a call like this > > $(call eval_vars,GCOV_PROFILE_,a/b/c) I just hooked it up and it works perfectly - I owe you a beer :) > would evaluate to the concatenation of the contents of the following > variables: > > GCOV_PROFILE_a_b_c > GCOV_PROFILE_a_b > GCOV_PROFILE_a > > The first non-empty variable would then determine whether profiling > should be enabled for the associated source file or not. This would even > implement the correct order of precedence (specific to generic) > > Not sure if this amount of magic is suitable for kbuild though. An > alternative, less complex approach would be to move this decision logic > to a helper script. Now that I've spent a couple days starting to wrap my head more around make, it doesn't look terribly magic to me. I'd hate to have to spawn off a subshell for this.
