Refractor and simplify Makefile in C code.

C/Makefile

@@ -1,26 +1,38 @@
 C_SRC=$(wildcard src/*.c)
-C_OBJ=$(patsubst src/%.c, $(BUILD_DIR)/%.o, $(C_SRC))
+C_OBJ=$(patsubst src/%.c, build/%.o, $(C_SRC))
 
 SLIB=$(BUILD_DIR)/$(LIBNAME).a
 
-.PHONY: headers sources build static shared clean
+.PHONY: headers sources build static shared clean ostype
 
-all: headers sources build static shared
+all: build static shared
 
 
+# ---------------------------------------------------------------------
+# SOURCES
 headers: 
 	make -C include
 
 sources: headers
 	make -C src sources
+# ---------------------------------------------------------------------
 
-build: headers sources
+
+# ---------------------------------------------------------------------
+# COMPILATION
+build: $(C_OBJ)
 	mkdir -p $(BUILD_DIR)
-	make -C src
 
 example: sources headers build
 	make -C example
 
+build/%.o: src/%.c
+	gcc -c -I./include $(CFLAGS_RELEASE) $(FPM_CFLAGS) $< -o $@
+# ---------------------------------------------------------------------
+
+
+# ---------------------------------------------------------------------
+# LINKING - STATIC and DYNAMIC LIBS
 static: build
 	ar -crs $(SLIB) $(C_OBJ)
 
@@ -34,6 +46,9 @@ shared_darwin:
 
 shared_windows: 
 	$(CC) -shared $(FPM_LDFLAGS) -o $(BUILD_DIR)/$(LIBNAME).dll -Wl,--out-implib=$(BUILD_DIR)/$(LIBNAME).dll.a,--export-all-symbols,--enable-auto-import,--whole-archive $(BUILD_DIR)/$(LIBNAME).a -Wl,--no-whole-archive
+# ---------------------------------------------------------------------
+
+
 
 clean:
 	rm -rf ./build/*

C/src/Makefile

@@ -29,9 +29,5 @@ codata_constants_2018.c: $(AST_DIR)/codata_2018.toml
 codata_constants_2022.c: $(AST_DIR)/codata_2022.toml
 	$(PY) $(GEN) $< $@
 
-$(CBUILD_DIR)/%.o: %.c
-	gcc -c -I../include $(CFLAGS_RELEASE) $(FPM_CFLAGS) $< -o $@
-
-
 clean:
 	rm -rf $(C_SRC)