Fix.

Author: sisshiki1969

monoasm/src/jit_memory.rs

@@ -450,6 +450,10 @@ impl JitMemory {
                 for target in std::mem::take(&mut rel.target) {
                     self.write_reloc(src_page, src_pos, target);
                 }
+            } else {
+                if !rel.target.is_empty() {
+                    panic!("DestLabel has no position binding.");
+                }
             }
         }
         self.labels = reloc;