Re: make 3.81rc2: automatic variables strip leading "./"

[Angel Tsankov]

>  at> Thank you very much for the detailed explanation, but I have to
>  at> disappoint you - it was not necessary since I perfectly understand
>  at> the issue.
>
> OK, sorry.
>
>  at> I need a way to compare lists to work around an inconvenience that
>  at> this issue poses and this inconvenience happens to involve
>  at> patsubst.
>
> Well, I guess I don't understand what you're asking.  You'll need to be
> more clear or, preferably, provide a specific example.

OK, here it is. Consider the following makefile:

DEPENDENCIES_FROM_SOURCES = $(patsubst 
$(SOURCE_PATH)/%$(SOURCE_FILE_EXT),$(DEPENDENCY_PATH)/%$(DEPENDENCY_FILE_EXT),$(1))

$(INTERMEDIATE_PATH)/%$(OBJECT_FILE_EXT): \
$(SOURCE_PATH)/%$(SOURCE_FILE_EXT)   \
$(DEPENDENCY_PATH)/%$(DEPENDENCY_FILE_EXT)
@$(eval DEPENDENCY_FILE := $(call DEPENDENCIES_FROM_SOURCES,$<))

# On the last line "$<" is canonical. Now conisder the case when SOURCE_PATH is "." - DEPENDENCIES_FROM_SOURCES does not perform any 
substitution, which is a problem.
# In order to work around it, I consider cononizing the argument to 
DEPENDENCIES_FROM_SOURCE, e.g. like this:

CANONIZE = \
$(eval TEMP := $(patsubst ./%,%,$(1))) \
$(if $(TEMP)==$(1),$(call CANONICALIZE,TEMP))

# The problem with this approach is that I need to compare two lists for equality, or check if patsubst has performed any 
substitution.