Enable loading native libraries with RTLD_DEEPBIND

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 537 matching lines @@
     "metrics/sample_map.h",
     "metrics/sample_vector.cc",
     "metrics/sample_vector.h",
     "metrics/sparse_histogram.cc",
     "metrics/sparse_histogram.h",
     "metrics/statistics_recorder.cc",
     "metrics/statistics_recorder.h",
     "metrics/user_metrics.cc",
     "metrics/user_metrics.h",
     "metrics/user_metrics_action.h",
+    "native_library.cc",
     "native_library.h",
     "native_library_ios.mm",
     "native_library_mac.mm",
     "native_library_posix.cc",
     "native_library_win.cc",
     "nix/mime_util_xdg.cc",
     "nix/mime_util_xdg.h",
     "nix/xdg_util.cc",
     "nix/xdg_util.h",
     "numerics/safe_conversions.h",
@@ skipping 482 matching lines @@
   if (!use_sysroot && (is_android || is_linux)) {
     libs = [ "atomic" ]
   }
 
   if (use_experimental_allocator_shim) {
     # The allocator shim is part of the base API. This is to allow clients of
     # base should to install hooks into the allocator path.
     public_deps += [ "//base/allocator:unified_allocator_shim" ]
   }
 
+  if (use_gold && !is_android) {

[Primiano Tucci (use gerrit), 2016/08/24 22:14:08]

why use_gold? The linker used to build the binary shouldn't make a different.
the behavior is given by the loader, not the linker (unless there is some gold
feature I'm not considering). 
IMHO this should be if (is_linux).
But at this point you don't need the define and you can just use #if
defined(OS_LINUX)

[Ken Rockot(use gerrit already), 2016/08/24 23:23:57]

Well, this was failing on cast_shell_linux, and the only relevant difference I
could find between is_chromecast true/false is that we don't use gold for
is_chromecast=true. In that configuration, we don't see the default global
behavior.

+    defines += [ "EXPECT_GLOBAL_RTLD_BEHAVIOR" ]

[Primiano Tucci (use gerrit), 2016/08/24 22:14:09]

adding defines to an entire target is discouraged, see brett's thread
[chromium-dev] New system for feature enable/disable flags [1]
If you really want this define, you need to use a buildflag_header here. See
allocator:features in base/allocator/BUILD.gn as an example [2]


[1]
https://groups.google.com/a/chromium.org/d/msg/chromium-dev/5c4ySpPsV14/JJfAe...
[2]
https://cs.chromium.org/chromium/src/base/allocator/BUILD.gn?q=allocator+feat...

[Ken Rockot(use gerrit already), 2016/08/24 23:23:57]

Oops. This was meant to be only on the base_unittests target (fixed). Is it more
palatable there given that it's a leaf target?

+  }
+
   # Allow more direct string conversions on platforms with native utf8
   # strings
   if (is_mac || is_ios || is_chromeos || is_chromecast) {
     defines += [ "SYSTEM_NATIVE_UTF8" ]
   }
 
   # Android.
   if (is_android) {
     sources -= [
       "debug/stack_trace_posix.cc",
@@ skipping 58 matching lines @@
       "files/important_file_writer.cc",
       "files/important_file_writer.h",
       "files/scoped_temp_dir.cc",
       "memory/discardable_memory.cc",
       "memory/discardable_memory.h",
       "memory/discardable_memory_allocator.cc",
       "memory/discardable_memory_allocator.h",
       "memory/discardable_shared_memory.cc",
       "memory/discardable_shared_memory.h",
       "memory/shared_memory_posix.cc",
+      "native_library.cc",
       "native_library_posix.cc",
       "path_service.cc",
       "process/kill.cc",
       "process/kill.h",
       "process/memory.cc",
       "process/memory.h",
       "process/process_iterator.cc",
       "process/process_iterator.h",
       "process/process_metrics.cc",
       "process/process_metrics_posix.cc",
@@ skipping 872 matching lines @@
     ":message_loop_tests",
     "//base/allocator:features",
     "//base/test:run_all_base_unittests",
     "//base/test:test_support",
     "//base/third_party/dynamic_annotations",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/icu",
   ]
 
+  data_deps = [
+    ":native_library_test_library",
+  ]
+
   if (is_ios || is_mac) {
     deps += [ ":base_unittests_arc" ]
   }
 
   public_deps = [
     ":base_unittests_bundle_data",
   ]
 
   # Some unittests depend on the ALLOCATOR_SHIM macro.
   configs += [ "//base/allocator:allocator_shim_define" ]
@@ skipping 106 matching lines @@
       # data += [ "$root_out_dir/base_unittests.dSYM/" ]
     }
   }
 
   if (use_cfi_cast) {
     # TODO(krasin): remove CFI_CAST_CHECK, see https://crbug.com/626794.
     defines += [ "CFI_CAST_CHECK" ]
   }
 }
 
+shared_library("native_library_test_library") {
+  sources = [
+    "native_library_test_library.cc",
+  ]
+}
+
 action("build_date") {
   script = "//build/write_build_date_header.py"
 
   # Force recalculation if there's been a change.
   inputs = [
     "//build/util/LASTCHANGE",
   ]
   outputs = [
     "$target_gen_dir/generated_build_date.h",
   ]
@@ skipping 279 matching lines @@
   android_library("base_java_unittest_support") {
     deps = [
       ":base_java",
     ]
     java_files = [
       "test/android/java/src/org/chromium/base/ContentUriTestUtils.java",
       "test/android/java/src/org/chromium/base/TestSystemMessageHandler.java",
     ]
   }
 }