Implemented linking to a dummy ASan runtime

runtime/szrt_asan.c

+//===- subzero/runtime/szrt_asan.c - AddressSanitizer Runtime -----*- C -*-===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief Provides the AddressSanitizer runtime.
+///
+/// Exposes functions for initializing the shadow memory region and managing it
+/// on loads, stores, and allocations.
+///
+//===----------------------------------------------------------------------===//
+
+#include <stdio.h>
+
+// TODO(tlively): Define and implement this library
+void __asan_init(void) {
+  printf("Set up shadow memory here\n");
+  return;
+}