Index: compiler-rt/test/fuzzer/InitializeTest.cpp
===================================================================
--- compiler-rt/test/fuzzer/InitializeTest.cpp
+++ compiler-rt/test/fuzzer/InitializeTest.cpp
@@ -9,7 +9,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-static char *argv0;
+static char *argv0 = NULL;
 
 extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv) {
   assert(*argc > 0);
@@ -20,8 +20,7 @@
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
   assert(argv0);
-  if (Size == strlen(argv0) &&
-      !memmem(Data, Size, argv0, Size)) {
+  if (argv0 && Size >= 4 && !memcmp(Data, "fuzz", 4)) {
     fprintf(stderr, "BINGO %s\n", argv0);
     exit(1);
   }
Index: compiler-rt/test/fuzzer/initialize.test
===================================================================
--- compiler-rt/test/fuzzer/initialize.test
+++ compiler-rt/test/fuzzer/initialize.test
@@ -1,4 +1,4 @@
-# FIXME: Disabled on Windows because memmem is a GNU extension.
+# FIXME: Disabled on Windows since LLVMFuzzerInitialize does not yet work.
 UNSUPPORTED: windows
 CHECK: BINGO
 RUN: %cpp_compiler %S/InitializeTest.cpp -o %t-InitializeTest