Update Makefile to remove warning when compiling `fmpi_futhark_entry.c`

Makefile

@@ -41,8 +41,10 @@ CFLAGS = -Wall -Walloc-zero -Warith-conversion -Warray-bounds=2 \
 -funsafe-loop-optimizations -ftrack-macro-expansion=0 -std=c17
 ifeq ($(BUILD_MODE),debug)
     CFLAGS += -g3 -Og
+	CFLAGS_FUTHARK += -g3 -Og
 else
     CFLAGS += -O2 -fstack-protector-all -fstack-protector-strong -DNDEBUG
+	CFLAGS_FUTHARK += -O2 -DNDEBUG
 endif
 CFLAGS += -Iinclude $(MPI_INCDIRS)
 CPPFLAGS = -MMD -MT $@ -MP -MF build/$(BUILD_MODE)/obj/$*.d
@@ -64,6 +66,9 @@ all_debug:
 all_release:
 	$(MAKE) all BUILD_MODE=release
 
+build/$(BUILD_MODE)/obj/fmpi_futhark_entry.o: fmpi_futhark_entry.c build/$(BUILD_MODE)/obj/fmpi_futhark_entry.d | build/$(BUILD_MODE)/obj
+	$(CC) $< -o $@ -c -fPIC $(CFLAGS_FUTHARK) -MMD -MT $@ -MP -MF build/$(BUILD_MODE)/obj/fmpi_futhark_entry.d
+
 build/$(BUILD_MODE)/obj/%.o: %.c build/$(BUILD_MODE)/obj/%.d | build/$(BUILD_MODE)/obj
 	$(CC) $< -o $@ -c -fPIC $(CFLAGS) $(CPPFLAGS)
 

examples/array_sum/.gitignore

+*.json
+*.o
+*.pp
 as-debug
 as-release
 as.c
 as.h
-as.json
-main.pp

examples/array_sum/Makefile

@@ -12,9 +12,15 @@ all_debug:
 all_release:
 	$(MAKE) all BUILD_MODE=release
 
-as-$(BUILD_MODE): main.c as.c as.h
+as-$(BUILD_MODE): main-$(BUILD_MODE).o as-$(BUILD_MODE).o
 	$(CC) $^ -o $@ $(CFLAGS) $(LDFLAGS) $(LDLIBS)
 
+main-$(BUILD_MODE).o: main.c as.h
+	$(CC) $< -o $@ -c -fPIC $(CFLAGS)
+
+as-$(BUILD_MODE).o: as.c as.h
+	$(CC) $< -o $@ -c -fPIC $(CFLAGS_FUTHARK)
+
 as.h as.c &: as.fut
 	futhark c --library $<
 
@@ -35,10 +41,14 @@ clean-all: clean-debug clean-release clean-futhark
 .PHONY: clean-debug
 clean-debug:
 	rm -f as-debug
+	rm -f as-debug.o
+	rm -f main-debug.o
 
 .PHONY: clean-release
 clean-release:
 	rm -f as-release
+	rm -f as-release.o
+	rm -f main-release.o
 
 .PHONY: clean-futhark
 clean-futhark: