Add more vars to print-vars

Author: flanglet

src/Makefile

@@ -178,8 +178,13 @@ endif
 
 print-vars:
 	@echo "OS=$(OS)"
+	@echo "APP=$(APP)"
+	@echo "CXX=$(CXX)"
+	@echo "CXXFLAGS=$(CXXFLAGS)"
+	@echo "LDFLAGS=$(LDFLAGS)"
 	@echo "INSTALL_DIR=$(INSTALL_DIR)"
 
+
 install: $(STATIC_LIB) $(SHARED_LIB) $(APP)
 ifeq ($(OS),Windows_NT)
 	copy /Y ..\bin\$(APP)$(PROG_SUFFIX) $(INSTALL_DIR)