Fix ssd1306 compilation on avr-gcc 10 (#9267)

2 files changed, 3 insertions, 1 deletions

diff --git a/keyboards/helix/local_drivers/ssd1306.c b/keyboards/helix/local_drivers/ssd1306.c
index 00b2fb0ee..c6fc4b785 100644
--- a/keyboards/helix/local_drivers/ssd1306.c
+++ b/keyboards/helix/local_drivers/ssd1306.c
@@ -16,6 +16,8 @@
 #include "sendchar.h"
 #include "timer.h"
 
+struct CharacterMatrix display;
+
 // Set this to 1 to help diagnose early startup problems
 // when testing power-on with ble.  Turn it off otherwise,
 // as the latency of printing most of the debug info messes
diff --git a/keyboards/helix/local_drivers/ssd1306.h b/keyboards/helix/local_drivers/ssd1306.h
index f9f91c6fe..bcb30f885 100644
--- a/keyboards/helix/local_drivers/ssd1306.h
+++ b/keyboards/helix/local_drivers/ssd1306.h
@@ -66,7 +66,7 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
+extern struct CharacterMatrix display;
 
 bool iota_gfx_init(bool rotate);
 void iota_gfx_task(void);