Roll clang 318667:321529.

Created by patching in
https://chromium-review.googlesource.com/c/chromium/src/+/835358 and
manually editting the revision in update.py.

TBR-ing rsesek@ again for the sandbox changes.
TBR-ing bretw@ again for the ppapi adapter LLD warning suppression.

I will manually build and test net_unittests after uploading to goma,
but I've built this clang revision locally and they are not flaky for
me.

R=inglorion@chromium.org,hans@chromium.org
TBR=rsesek@chromium.org,brettw@chromium.org

Bug: 787920, 797267, 797168
Cq-Include-Trybots: master.tryserver.chromium.android:android_arm64_dbg_recipe;master.tryserver.chromium.android:android_compile_mips_dbg;master.tryserver.chromium.android:android_compile_x64_dbg;master.tryserver.chromium.android:android_compile_x86_dbg
Change-Id: Ifd25c014e79ad7a5d4533941ae7fd74a86860191
Reviewed-on: https://chromium-review.googlesource.com/845700Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Hans Wennborg <hans@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Reviewed-by: Reid Kleckner <rnk@chromium.org>
Commit-Queue: Reid Kleckner <rnk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#526748}

build/config/BUILDCONFIG.gn

@@ -525,6 +525,9 @@ default_compiler_configs = [
   "//build/config/compiler:default_optimization",
   "//build/config/compiler:default_stack_frames",
   "//build/config/compiler:default_symbols",
+
+  # TODO(crbug.com/795158): Remove once libwidevinecdmadapter.so is fixed.
+  "//build/config/compiler:default_fatal_linker_warnings",
   "//build/config/compiler:no_exceptions",
   "//build/config/compiler:no_rtti",
   "//build/config/compiler:runtime_library",

build/config/compiler/BUILD.gn

@@ -265,16 +265,6 @@ config("compiler") {
         cflags += [ "-fstack-protector" ]
       }
     }
-
-    # Linker warnings.
-    if (fatal_linker_warnings && !(is_chromeos && current_cpu == "arm") &&
-        !(is_android && use_order_profiling) && !is_mac && !is_ios &&
-        current_os != "aix") {
-      # TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
-      # TODO(lizeb,pasko): Fix link errors when linking with order_profiling=1
-      # crbug.com/485542
-      ldflags += [ "-Wl,--fatal-warnings" ]
-    }
   }
 
   # Eliminate build metadata (__DATE__, __TIME__ and __TIMESTAMP__) for
@@ -2050,3 +2040,19 @@ if (is_ios || is_mac) {
     cflags_objcc = common_flags
   }
 }
+
+# Default linker warnings.
+config("default_fatal_linker_warnings") {
+  ldflags = []
+
+  # Linker warnings.
+  if (!is_win && fatal_linker_warnings &&
+      !(is_chromeos && current_cpu == "arm") &&
+      !(is_android && use_order_profiling) && !is_mac && !is_ios &&
+      current_os != "aix") {
+    # TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
+    # TODO(lizeb,pasko): Fix link errors when linking with order_profiling=1
+    # crbug.com/485542
+    ldflags += [ "-Wl,--fatal-warnings" ]
+  }
+}

media/cdm/ppapi/ppapi_cdm_adapter.gni

@@ -2,6 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/compiler/compiler.gni")
+
 # This template defines a CDM adapter target. Just use this as you would a
 # normal target and everything should work correctly.
 template("ppapi_cdm_adapter") {
@@ -61,6 +63,11 @@ template("ppapi_cdm_adapter") {
     if (is_linux) {
       # CDM adapter depends on a CDM in component and non-component builds.
       configs += [ "//build/config/gcc:rpath_for_built_shared_libraries" ]
+
+      if (use_lld) {
+        # TODO(crbug.com/795158) LLD warns about libwidevinecdm.so
+        configs -= [ "//build/config/compiler:default_fatal_linker_warnings" ]
+      }
     }
 
     # TODO(jschuh) crbug.com/167187

sandbox/linux/tests/unit_tests.cc

@@ -135,16 +135,7 @@ void UnitTests::RunTestInProcess(SandboxTestRunner* test_runner,
   // We need to fork(), so we can't be multi-threaded, as threads could hold
   // locks.
   int num_threads = CountThreads();
-#if !defined(THREAD_SANITIZER)
   const int kNumExpectedThreads = 1;
-#else
-  // Under TSAN, there is a special helper thread. It should be completely
-  // invisible to our testing, so we ignore it. It should be ok to fork()
-  // with this thread. It's currently buggy, but it's the best we can do until
-  // there is a way to delay the start of the thread
-  // (https://code.google.com/p/thread-sanitizer/issues/detail?id=19).
-  const int kNumExpectedThreads = 2;
-#endif
 
   // The kernel is at liberty to wake a thread id futex before updating /proc.
   // If another test running in the same process has stopped a thread, it may

tools/clang/scripts/update.py

@@ -27,7 +27,7 @@ import zipfile
 # Do NOT CHANGE this if you don't know what you're doing -- see
 # https://chromium.googlesource.com/chromium/src/+/master/docs/updating_clang.md
 # Reverting problematic clang rolls is safe, though.
-CLANG_REVISION = '318667'
+CLANG_REVISION = '321529'
 
 use_head_revision = bool(os.environ.get('LLVM_FORCE_HEAD_REVISION', '0')
                          in ('1', 'YES'))