I'm wondering whether it might be reasonable to skip the redundant-recipe warnings if the recipes are identical anyway. Test case:

% cat makefile
.PHONY: all
all:
foo:; touch $@
foo:; touch $@

% make
makefile:5: warning: overriding recipe for target 'foo'
makefile:4: warning: ignoring old recipe for target 'foo'
make: Nothing to be done for 'all'.

It looks like this might be avoidable with a strcmp in read.c around line 2113 (in current SCM) though I'm not in a position to try it now.

This comes up because I have various macros and helper makefiles which generate rules to create directory paths. The recipe to create a directory will in all cases be "mkdir $@" in my use case but when multiple macros end up generating identical rules these spurious warnings are still printed. Of course it can be programmed around but I wonder whether it's worth giving the warning at all here.