Don't add -lrt when linking ASan/TSan/MSan binaries.

build/common.gypi

 # 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 3380 matching lines @@
             'target_conditions': [
               ['_toolset=="target"', {
                 'cflags': [
                   '-fno-omit-frame-pointer',
                   '-gline-tables-only',
                 ],
                 'ldflags!': [
                   # Functions interposed by the sanitizers can make ld think
                   # that some libraries aren't needed when they actually are,
                   # http://crbug.com/234010. As workaround, disable --as-needed.
                   '-Wl,--as-needed',

[Nico, 2014/06/17 20:48:09]

Can this be removed now too? Should http://llvm.org/bugs/show_bug.cgi?id=15823
be marked as fixed?

                 ],
                 'defines': [
                   'MEMORY_TOOL_REPLACES_ALLOCATOR',
                 ],
               }],
-              ['_toolset=="target" and OS=="linux"', {
-                'ldflags': [
-                  # http://crbug.com/234010.
-                  '-lrt',
-                ],
-              }],
             ],
           }],
           ['asan==1', {
             'target_conditions': [
               ['_toolset=="target"', {
                 'cflags': [
                   '-fsanitize=address',
                   '-w',  # http://crbug.com/162783
                 ],
                 'ldflags': [
@@ skipping 1365 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }