2 files changed, 48 insertions, 3 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/buildeventstream/AbortedEvent.java b/src/main/java/com/google/devtools/build/lib/buildeventstream/AbortedEvent.java
index 5816ecd3bd..0638c29552 100644
--- a/src/main/java/com/google/devtools/build/lib/buildeventstream/AbortedEvent.java
+++ b/src/main/java/com/google/devtools/build/lib/buildeventstream/AbortedEvent.java
@@ -16,7 +16,7 @@ package com.google.devtools.build.lib.buildeventstream;
 
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.cmdline.Label;
-
+import java.util.Collection;
 import javax.annotation.Nullable;
 
 /** A {@link BuildEvent} reporting an event not coming due to the build being aborted. */
@@ -26,15 +26,34 @@ public class AbortedEvent extends GenericBuildEvent {
   @Nullable private final Label label;
 
   public AbortedEvent(
-      BuildEventId id, BuildEventStreamProtos.Aborted.AbortReason reason, String description,
+      BuildEventId id,
+      Collection<BuildEventId> children,
+      BuildEventStreamProtos.Aborted.AbortReason reason,
+      String description,
       @Nullable Label label) {
-    super(id, ImmutableList.<BuildEventId>of());
+    super(id, children);
     this.reason = reason;
     this.description = description;
     this.label = label;
   }
 
   public AbortedEvent(
+      BuildEventId id,
+      BuildEventStreamProtos.Aborted.AbortReason reason,
+      String description,
+      @Nullable Label label) {
+    this(id, ImmutableList.<BuildEventId>of(), reason, description, label);
+  }
+
+  public AbortedEvent(
+      BuildEventId id,
+      Collection<BuildEventId> children,
+      BuildEventStreamProtos.Aborted.AbortReason reason,
+      String description) {
+    this(id, children, reason, description, null);
+  }
+
+  public AbortedEvent(
       BuildEventId id, BuildEventStreamProtos.Aborted.AbortReason reason, String description) {
     this(id, reason, description, null);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java b/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
index 3353d577e8..b393af0cb8 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
@@ -254,6 +254,27 @@ public class BuildEventStreamer implements EventHandler {
     }
   }
 
+  /**
+   * If some events are blocked on the absence of a build_started event, generate such an event;
+   * moreover, make that artificial start event announce all events blocked on it, as well as the
+   * {@link BuildCompletingEvent} that caused the early end of the stream.
+   */
+  private void clearMissingStartEvent(BuildEventId id) {
+    if (pendingEvents.containsKey(BuildEventId.buildStartedId())) {
+      ImmutableSet.Builder<BuildEventId> children = ImmutableSet.<BuildEventId>builder();
+      children.add(ProgressEvent.INITIAL_PROGRESS_UPDATE);
+      children.add(id);
+      children.addAll(
+          pendingEvents
+              .get(BuildEventId.buildStartedId())
+              .stream()
+              .map(BuildEvent::getEventId)
+              .collect(ImmutableSet.<BuildEventId>toImmutableSet()));
+      buildEvent(
+          new AbortedEvent(BuildEventId.buildStartedId(), children.build(), abortReason, ""));
+    }
+  }
+
   /** Clear pending events by generating aborted events for all their requisits. */
   private void clearPendingEvents() {
     while (!pendingEvents.isEmpty()) {
@@ -404,6 +425,11 @@ public class BuildEventStreamer implements EventHandler {
       }
     }
 
+    if (event instanceof BuildCompletingEvent
+        && !event.getEventId().equals(BuildEventId.buildStartedId())) {
+      clearMissingStartEvent(event.getEventId());
+    }
+
     post(event);
 
     // Reconsider all events blocked by the event just posted.