diff --git a/arch/sandbox/include/asm/u-boot-sandbox.h b/arch/sandbox/include/asm/u-boot-sandbox.h
index b2b8e36455..798d003077 100644
--- a/arch/sandbox/include/asm/u-boot-sandbox.h
+++ b/arch/sandbox/include/asm/u-boot-sandbox.h
@@ -26,6 +26,8 @@ int cleanup_before_linux(void);
 /* drivers/video/sandbox_sdl.c */
 int sandbox_lcd_sdl_early_init(void);
 
+struct udevice;
+
 /**
  * pci_map_physmem() - map a PCI device into memory
  *