Added fix for undefined instruction usage fault
diff --git a/core/src/entry_point/start_item_arm.rs b/core/src/entry_point/start_item_arm.rs
index c9390f6..43e259f 100644
--- a/core/src/entry_point/start_item_arm.rs
+++ b/core/src/entry_point/start_item_arm.rs
@@ -23,7 +23,8 @@
// the Program Counter) will match the intended location of .start. We
// don't have an easy way to signal an error, so for now we just yield
// if the location is wrong.
- sub r4, pc, #4 // r4 = pc
+ mov r4, pc
+ sub r4, r4, #4 // r4 = pc
ldr r5, =.start // r5 = address of .start
cmp r4, r5
beq .Lstack_init // Jump to stack initialization if pc was correct
