diff --git a/Makefile b/Makefile
index ff87147611..19d2d5d4cb 100644
--- a/Makefile
+++ b/Makefile
@@ -1299,6 +1299,13 @@ SPATCH_INCLUDE_FLAGS = --all-includes
 SPATCH_FLAGS =
 SPATCH_TEST_FLAGS =
 
+# If *.o files are present, have "coccicheck" depend on them, with
+# COMPUTE_HEADER_DEPENDENCIES this will speed up the common-case of
+# only needing to re-generate coccicheck results for the users of a
+# given API if it's changed, and not all files in the project. If
+# COMPUTE_HEADER_DEPENDENCIES=no this will be unset too.
+SPATCH_USE_O_DEPENDENCIES = YesPlease
+
 # Rebuild 'coccicheck' if $(SPATCH), its flags etc. change
 TRACK_SPATCH_DEFINES =
 TRACK_SPATCH_DEFINES += $(SPATCH)
@@ -3176,14 +3183,18 @@ COCCI_TEST_RES = $(wildcard contrib/coccinelle/tests/*.res)
 	$(call mkdir_p_parent_template)
 	$(QUIET_GEN) >$@
 
+ifeq ($(COMPUTE_HEADER_DEPENDENCIES),no)
+SPATCH_USE_O_DEPENDENCIES =
+endif
 define cocci-rule
 
 ## Rule for .build/$(1).patch/$(2); Params:
 # $(1) = e.g. "free.cocci"
 # $(2) = e.g. "grep.c"
+# $(3) = e.g. "grep.o"
 COCCI_$(1:contrib/coccinelle/%.cocci=%) += .build/$(1).patch/$(2)
 .build/$(1).patch/$(2): GIT-SPATCH-DEFINES
-.build/$(1).patch/$(2): .build/contrib/coccinelle/FOUND_H_SOURCES
+.build/$(1).patch/$(2): $(if $(and $(SPATCH_USE_O_DEPENDENCIES),$(wildcard $(3))),$(3),.build/contrib/coccinelle/FOUND_H_SOURCES)
 .build/$(1).patch/$(2): $(1)
 .build/$(1).patch/$(2): .build/$(1).patch/% : %
 	$$(call mkdir_p_parent_template)
@@ -3200,7 +3211,7 @@ endef
 
 define cocci-matrix
 
-$(foreach s,$(COCCI_SOURCES),$(call cocci-rule,$(1),$(s)))
+$(foreach s,$(COCCI_SOURCES),$(call cocci-rule,$(c),$(s),$(s:%.c=%.o)))
 endef
 
 ifdef COCCI_GOALS
diff --git a/contrib/coccinelle/README b/contrib/coccinelle/README
index f0e80bd7f0..09ea8298e1 100644
--- a/contrib/coccinelle/README
+++ b/contrib/coccinelle/README
@@ -41,3 +41,19 @@ There are two types of semantic patches:
 
    This allows to expose plans of pending large scale refactorings without
    impacting the bad pattern checks.
+
+Git-specific tips & things to know about how we run "spatch":
+
+ * The "make coccicheck" will piggy-back on
+   "COMPUTE_HEADER_DEPENDENCIES". If you've built a given object file
+   the "coccicheck" target will consider its depednency to decide if
+   it needs to re-run on the corresponding source file.
+
+   This means that a "make coccicheck" will re-compile object files
+   before running. This might be unexpected, but speeds up the run in
+   the common case, as e.g. a change to "column.h" won't require all
+   coccinelle rules to be re-run against "grep.c" (or another file
+   that happens not to use "column.h").
+
+   To disable this behavior use the "SPATCH_USE_O_DEPENDENCIES=NoThanks"
+   flag.