Use diffprereqs files as dependencies, not FORCE

[Shushe] / GNUmakefile

diff --git a/GNUmakefile b/GNUmakefile
index 94f5efa26f5f4a33cbc62a59d406da3ce08e3ed8..c654ddbfcc160d9423a1858440c7bcb6cbb72b6c 100644 (file)
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -348,16 +348,16 @@ ifeq ($(MODE),urn:fdc:ladys.computer:20231231:Shu1She4:mode:default)
 # Non·empty if `help´ or `clean´, and no targets other than `help´ or `clean´, were specified as goals on the commandline.
 override notbuilding := $(and $(filter help clean,$(MAKECMDGOALS)),$(call not,$(filter-out help clean,$(MAKECMDGOALS))))
 
-# (callable) Test to see if the prerequisites provided by the second argument matches the value in the file corresponding to the first argument in `$(BUILDDIR)/lastprereqs´.
-# If not, save the new value and then add FORCE.
-# Return them regardless.
+# (callable) Tests to see if the prerequisites provided by the second argument matches the value in the file corresponding to the first argument in `$(BUILDDIR)/lastprereqs´.
+# If not, saves the new value.
+# Returns the values plus the file in `$(BUILDDIR)/lastprereqs´, which will always be newer than the target if there was a change.
 #
 # Calling this variable is useful when a given target should be updated whenever its list of prerequisites changes in addition to whenever there is a change to one of its prerequisites.
 #
 # If `$(notbuilding)´ is non·empty, this variable produces no result to avoid unnecessary work.
 #
 # ☡ This variable creates at least one subshell every time it is computed.
-override diffprereqs = $(if $(notbuilding),,$(if $(subst $(shell $(CAT) $(call quote,$(BUILDDIR)/lastprereqs/$1) 2>>/dev/null || :),,$2),$2 FORCE$(and $(shell $(call ensuredirectory,$(BUILDDIR)/lastprereqs) && $(PRINTF) '%s\n' $(call quote,$2) >|$(BUILDDIR)/lastprereqs/$1),),$2))
+override diffprereqs = $(if $(notbuilding),,$(and $(subst $(shell $(CAT) $(call quote,$(BUILDDIR)/lastprereqs/$1) 2>>/dev/null || :),,$2),$(shell $(call ensuredirectory,$(BUILDDIR)/lastprereqs) && $(PRINTF) '%s\n' $(call quote,$2) >|$(BUILDDIR)/lastprereqs/$1),)$2 $(BUILDDIR)/lastprereqs/$1)
 
 # (callable) Escape special characters for use in X·M·L.
 override xmlesc = $(subst >,&gt;,$(subst <,&lt;,$(subst &,&amp;,$1)))