Index: lib/asan/asan_mac.cc
===================================================================
--- lib/asan/asan_mac.cc
+++ lib/asan/asan_mac.cc
@@ -67,6 +67,7 @@
 void __asan_init();
 
 static const char kDyldInsertLibraries[] = "DYLD_INSERT_LIBRARIES";
+static const char kDylibSuffix[] = ".dylib";
 LowLevelAllocator allocator_for_env;
 
 // Change the value of the env var |name|, leaking the original value.
@@ -114,6 +115,15 @@
   uptr fname_len = internal_strlen(info.dli_fname);
   const char *dylib_name = StripModuleName(info.dli_fname);
   uptr dylib_name_len = internal_strlen(dylib_name);
+
+  // "Noinst" unit tests link the runtime statically. We can't re-exec there,
+  // because we have no dylib to insert. Wrappers don't work there (that's
+  // expected).
+  uptr suffix_len = internal_strlen(kDylibSuffix);
+  if (dylib_name_len < suffix_len ||
+      internal_strcmp(dylib_name + dylib_name_len - suffix_len, kDylibSuffix))
+    return;
+
   if (!dyld_insert_libraries ||
       !REAL(strstr)(dyld_insert_libraries, dylib_name)) {
     // DYLD_INSERT_LIBRARIES is not set or does not contain the runtime