[PATCH 3/5] coccinelle: exclude sha1dc source files from static analysis

["SZEDER Gábor" <szeder.dev@gmail.com>]

sha1dc is an external library, that we carry in-tree for convenience
or grab as a submodule, so there is no use in applying our semantic
patches to its source files.

Therefore, exclude sha1dc's source files from Coccinelle's static
analysis.

This change also makes the static analysis somewhat faster: presumably
because of the heavy use of repetitive macro declarations, applying
the semantic patches 'array.cocci' and 'swap.cocci' to 'sha1dc/sha1.c'
takes over half a minute each on my machine, which amounts to about a
third of the runtime of applying these two semantic patches to the
whole git source tree.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
---
 Makefile | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 8f509576e9..73e2d16926 100644
--- a/Makefile
+++ b/Makefile
@@ -2666,10 +2666,16 @@ check: command-list.h
 	fi
 
 C_SOURCES = $(patsubst %.o,%.c,$(C_OBJ))
-%.cocci.patch: %.cocci $(C_SOURCES)
+ifdef DC_SHA1_SUBMODULE
+COCCI_SOURCES = $(filter-out sha1collisiondetection/%,$(C_SOURCES))
+else
+COCCI_SOURCES = $(filter-out sha1dc/%,$(C_SOURCES))
+endif
+
+%.cocci.patch: %.cocci $(COCCI_SOURCES)
 	@echo '    ' SPATCH $<; \
 	ret=0; \
-	for f in $(C_SOURCES); do \
+	for f in $(COCCI_SOURCES); do \
 		$(SPATCH) --sp-file $< $$f $(SPATCH_FLAGS) || \
 			{ ret=$$?; break; }; \
 	done >$@+ 2>$@.log; \
-- 
2.18.0.408.g42635c01bc