GC plugin: have -Werror issue errors for inputs having only warnings.

tools/clang/blink_gc_plugin/BlinkGCPluginConsumer.cpp

 // Copyright 2015 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.
 
 #include "BlinkGCPluginConsumer.h"
 
 #include <algorithm>
 #include <set>
 
 #include "CheckDispatchVisitor.h"
@@ skipping 200 matching lines @@
       getErrorLevel(), kClassMustLeftMostlyDeriveGC);
   diag_class_requires_trace_method_ =
       diagnostic_.getCustomDiagID(getErrorLevel(), kClassRequiresTraceMethod);
   diag_base_requires_tracing_ =
       diagnostic_.getCustomDiagID(getErrorLevel(), kBaseRequiresTracing);
   diag_fields_require_tracing_ =
       diagnostic_.getCustomDiagID(getErrorLevel(), kFieldsRequireTracing);
   diag_class_contains_invalid_fields_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kClassContainsInvalidFields);
   diag_class_contains_invalid_fields_warning_ = diagnostic_.getCustomDiagID(
-      DiagnosticsEngine::Warning, kClassContainsInvalidFields);
+      getErrorLevel(), kClassContainsInvalidFields);
   diag_class_contains_gc_root_ =
       diagnostic_.getCustomDiagID(getErrorLevel(), kClassContainsGCRoot);
   diag_class_requires_finalization_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kClassRequiresFinalization);
   diag_class_does_not_require_finalization_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Warning, kClassDoesNotRequireFinalization);

[Nico, 2015/11/29 15:29:20]

Here too I suppose?

[sof, 2015/11/29 16:51:16]

It is too imprecise & noisy in its current state, so compiling with
warn-unneeded-finalizers=1 is better off generating a stream of warnings (which
you can then sift through for anything of value), rather than have the -Werror
build fail on first occurrence.

   diag_finalizer_accesses_finalized_field_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kFinalizerAccessesFinalizedField);
   diag_finalizer_eagerly_finalized_field_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kFinalizerAccessesEagerlyFinalizedField);
   diag_overridden_non_virtual_trace_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kOverriddenNonVirtualTrace);
   diag_missing_trace_dispatch_method_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kMissingTraceDispatchMethod);
   diag_missing_finalize_dispatch_method_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kMissingFinalizeDispatchMethod);
@@ skipping 1028 matching lines @@
 void BlinkGCPluginConsumer::NoteField(FieldDecl* field, unsigned note) {
   ReportDiagnostic(field->getLocStart(), note) << field;
 }
 
 void BlinkGCPluginConsumer::NoteOverriddenNonVirtualTrace(
     CXXMethodDecl* overridden) {
   ReportDiagnostic(overridden->getLocStart(),
                    diag_overridden_non_virtual_trace_note_)
       << overridden;
 }