diff --git a/tests/legacy/kernel/test_fp_sharing/nanokernel/src/main.c b/tests/legacy/kernel/test_fp_sharing/nanokernel/src/main.c
index 032c40e601e..3abef8f7060 100644
--- a/tests/legacy/kernel/test_fp_sharing/nanokernel/src/main.c
+++ b/tests/legacy/kernel/test_fp_sharing/nanokernel/src/main.c
@@ -123,7 +123,7 @@ void main(void)
 	unsigned char *store_ptr = (unsigned char *)&float_reg_set_store;
 	unsigned char *load_ptr = (unsigned char *)&float_reg_set_load;
 
-	volatile char volatile_stack_var;
+	volatile char volatile_stack_var = 0;
 
 	PRINT_DATA("Floating point sharing tests started\n");
 	PRINT_LINE;