diff --git a/Makefile b/Makefile
index 5348451..ae05b29 100644
--- a/Makefile
+++ b/Makefile
@@ -41,9 +41,9 @@ STM32F1_LIB = opencm3_stm32f1
 # source files (this will be populated using includes based DEPENDENCIES)
 CSRC = global.c
 # headers corresponding to source files
-CHDR = $(patsubst %.c,%.h,$(CSRC))
+CHDR = $(sort $(patsubst %.c,%.h,$(CSRC)))
 # objects compiled from source files
-OBJ = $(patsubst %.c,%.o,$(CSRC))
+OBJ = $(sort $(patsubst %.c,%.o,$(CSRC)))
 # figure out based on the main sources files which library files are used
 DEPENDENCIES = $(patsubst %,%.inc,$(FIRMWARE))
 # populates CSRC based on the library files used