Fix force_use function by using original slice ptr instead of stack reference

Author: phil-opp

api/src/lib.rs

@@ -136,6 +136,6 @@ macro_rules! entry_point {
 
 #[doc(hidden)]
 pub fn __force_use(slice: &[u8]) {
-    let force_use = &slice as *const _ as usize;
+    let force_use = slice.as_ptr() as usize;
     unsafe { core::arch::asm!("add {0}, 0", in(reg) force_use, options(nomem, nostack)) };
 }