Non-SFI NaCl: Fix browser_tests based on libc_free.c

chrome/test/data/nacl/nacl_test_data.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'includes': [
     '../../../../ppapi/ppapi_nacl_test_common.gypi',
   ],
   'targets': [
     {
@@ skipping 1121 matching lines @@
           # The program does not apply any dynamic relocations at start up,
           # so it cannot rely on relocations having been applied.
           # In addition, -fvisibility=hidden avoids creating some types
           # of relocation.
           'cflags': [
             '-fPIC',
             '-fvisibility=hidden',
 
             # Stack-Smashing protector does not work with libc-free context.
             '-fno-stack-protector',
+            # Optimizers may translate the original code to code which
+            # requires builtin functions and/or relocations. Specifically,
+            # the LLVM's optimizer translates for-loop based zero
+            # clear to memset.
+            '-O0',
           ],
           'cflags!': [
             # We filter these out because release_extra_cflags or another
             # such thing might be adding them in, and those options wind up
             # coming after the -fno-stack-protector we added above.
             '-fstack-protector',
             '-fstack-protector-all',
             '-fprofile-generate',
             '-finstrument-functions',
+            '-O2',
           ],
           'ldflags': [
             '-nostdlib',
             '-shared',
+            # This binary cannot relocate itself, so we should have no
+            # undefined references left.
+            '-Wl,--no-undefined',
           ],
           'ldflags!': [
             # Explicitly remove the -pthread flag to avoid a link time warning.
             '-pthread',
           ],
           'defines': [
             # The code depends on NaCl's headers. This is a macro for them.
             'NACL_LINUX=1',
           ],
           # For native_client/src/include/...
@@ skipping 43 matching lines @@
               'files': [
                 '>@(test_files)',
               ],
             },
           ],
         },
       ],
     }],
   ],
 }