diff --git a/src/arch/x86/include/mode_switch.h b/src/arch/x86/include/mode_switch.h
index 0c46da5..24efb1e 100644
--- a/src/arch/x86/include/mode_switch.h
+++ b/src/arch/x86/include/mode_switch.h
@@ -1,6 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
-#include <stddef.h>
 #include <stdint.h>
 
 #if ENV_X86_64
diff --git a/src/arch/x86/include/smm.h b/src/arch/x86/include/smm.h
index 739b7158..e6db9dc 100644
--- a/src/arch/x86/include/smm.h
+++ b/src/arch/x86/include/smm.h
@@ -1,6 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
-#include <stddef.h>
 #include <stdint.h>
 #include <cpu/x86/smm.h>