diff --git a/arch/xtensa/platforms/iss/console.c b/arch/xtensa/platforms/iss/console.c
index 854677d0c3f6..9141e3690731 100644
--- a/arch/xtensa/platforms/iss/console.c
+++ b/arch/xtensa/platforms/iss/console.c
@@ -43,6 +43,7 @@ static DEFINE_SPINLOCK(timer_lock);
 
 int errno;
 
+static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
 static int __simc (int a, int b, int c, int d, int e, int f)
 {
 	int ret;
diff --git a/arch/xtensa/platforms/iss/network.c b/arch/xtensa/platforms/iss/network.c
index d89fb18d7971..a2e252217428 100644
--- a/arch/xtensa/platforms/iss/network.c
+++ b/arch/xtensa/platforms/iss/network.c
@@ -107,6 +107,7 @@ struct iss_net_private {
 
 static int errno;
 
+static int __simc (int a, int b, int c, int d, int e, int f) __attribute__((__noinline__));
 static int __simc (int a, int b, int c, int d, int e, int f)
 {
 	int ret;