diff --git a/_common/Graphics/bitmask2rgba.c b/_common/Graphics/bitmask2rgba.c
index 93a210804..f46f043a3 100644
--- a/_common/Graphics/bitmask2rgba.c
+++ b/_common/Graphics/bitmask2rgba.c
@@ -154,7 +154,7 @@ void bitmask_set_bitblit_bg(uint8_t red, uint8_t green, uint8_t blue)
     s_bitblitBG.rgbBlue = blue;
 }
 
-void bitmask_reset_bitblit_bg()
+void bitmask_reset_bitblit_bg(void)
 {
     s_bitblitBG.rgbRed = 0;
     s_bitblitBG.rgbGreen = 0;
diff --git a/_common/Graphics/bitmask2rgba.h b/_common/Graphics/bitmask2rgba.h
index 30a6502e9..2de04ea34 100644
--- a/_common/Graphics/bitmask2rgba.h
+++ b/_common/Graphics/bitmask2rgba.h
@@ -57,7 +57,7 @@ extern void bitmask_set_bitblit_bg(uint8_t red, uint8_t green, uint8_t blue);
 /**
  * @brief Restore the default pseudo-background colour
  */
-extern void bitmask_reset_bitblit_bg();
+extern void bitmask_reset_bitblit_bg(void);
 
 #ifdef __cplusplus
 }