Revert "fortify: allow diagnostics without run-time checks"

This reverts commit d7e11b88531665de59de466bbc9ee6c480b00a4f.

Reason for revert: Breaks aosp_x86_64-eng. Will look into it and
unbreak when it's not almost midnight. :)

Change-Id: I21f76efe4d19c70d0b14630e441376d359a45b49
diff --git a/tests/Android.bp b/tests/Android.bp
index ee4f02e..1755053 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -312,20 +312,26 @@
     },
 }
 
-// Ensures that FORTIFY checks aren't run when ASAN is on.
-cc_test {
-    name: "bionic-fortify-runtime-asan-test",
+// If building this fails, then we have both FORTIFY and ASAN enabled, which
+// isn't desirable. (Ideally, we'd emit FORTIFY diagnostics even with ASAN
+// enabled, but that's not a reality today.) This is meant to be otherwise
+// unused.
+cc_test_library {
+    name: "fortify_disabled_for_asan",
     defaults: [
         "bionic_clang_fortify_tests_w_flags",
     ],
     cflags: [
         "-Werror",
         "-D_FORTIFY_SOURCE=2",
+        // "sanitize: address" doesn't work on platforms where libasan isn't
+        // enabled. Since the intent is just to build this, we can get away with
+        // passing this flag on its own.
+        "-fsanitize=address",
     ],
-    sanitize: {
-        address: true,
-    },
-    srcs: ["clang_fortify_asan.cpp"],
+    // Ignore that we don't have ASAN symbols linked in.
+    allow_undefined_symbols: true,
+    srcs: ["clang_fortify_tests.cpp"],
 }
 
 // Ensure we don't use FORTIFY'ed functions with the static analyzer/clang-tidy: