1 files changed, 36 insertions, 11 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/AbstractConfiguredTarget.java b/src/main/java/com/google/devtools/build/lib/analysis/AbstractConfiguredTarget.java
index 1e7deca5b9..b522bce19d 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/AbstractConfiguredTarget.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/AbstractConfiguredTarget.java
@@ -24,11 +24,13 @@ import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.events.Location;
 import com.google.devtools.build.lib.packages.ClassObjectConstructor;
 import com.google.devtools.build.lib.packages.PackageSpecification;
+import com.google.devtools.build.lib.packages.SkylarkClassObject;
 import com.google.devtools.build.lib.packages.SkylarkProviderIdentifier;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.syntax.ClassObject;
 import com.google.devtools.build.lib.syntax.EvalException;
 import com.google.devtools.build.lib.syntax.EvalUtils;
+import java.util.concurrent.atomic.AtomicReference;
 import javax.annotation.Nullable;
 
 /**
@@ -42,6 +44,9 @@ public abstract class AbstractConfiguredTarget
 
   private final NestedSet<PackageSpecification> visibility;
 
+  // Cached on-demand default provider
+  private final AtomicReference<DefaultProvider> defaultProvider = new AtomicReference<>();
+
   // Accessors for Skylark
   private static final String DATA_RUNFILES_FIELD = "data_runfiles";
   private static final String DEFAULT_RUNFILES_FIELD = "default_runfiles";
@@ -106,15 +111,13 @@ public abstract class AbstractConfiguredTarget
 
   @Override
   public Object getValue(String name) {
-    // Standard fields should be proxied to their default provider object
-    DefaultProvider defaultProvider =
-        (DefaultProvider) get(DefaultProvider.SKYLARK_CONSTRUCTOR.getKey());
     switch (name) {
       case FILES_FIELD:
       case DEFAULT_RUNFILES_FIELD:
       case DATA_RUNFILES_FIELD:
       case FilesToRunProvider.SKYLARK_NAME:
-        return defaultProvider.getValue(name);
+        // Standard fields should be proxied to their default provider object
+        return getDefaultProvider().getValue(name);
       case LABEL_FIELD:
         return getLabel();
       default:
@@ -130,14 +133,10 @@ public abstract class AbstractConfiguredTarget
           EvalUtils.getDataTypeName(key)));
     }
     ClassObjectConstructor constructor = (ClassObjectConstructor) key;
-    SkylarkProviders provider = getProvider(SkylarkProviders.class);
-    if (provider != null) {
-      Object declaredProvider = provider.getDeclaredProvider(constructor.getKey());
-      if (declaredProvider != null) {
-        return declaredProvider;
-      }
+    Object declaredProvider = get(constructor.getKey());
+    if (declaredProvider != null) {
+      return declaredProvider;
     }
-    // Either provider or declaredProvider is null
     throw new EvalException(loc, String.format(
         "Object of type Target doesn't contain declared provider %s",
         constructor.getPrintableName()));
@@ -175,4 +174,30 @@ public abstract class AbstractConfiguredTarget
         FILES_FIELD,
         FilesToRunProvider.SKYLARK_NAME);
   }
+
+  private DefaultProvider getDefaultProvider() {
+    if (defaultProvider.get() == null) {
+      defaultProvider.compareAndSet(
+          null,
+          DefaultProvider.build(
+              getProvider(RunfilesProvider.class),
+              getProvider(FileProvider.class),
+              getProvider(FilesToRunProvider.class)));
+    }
+    return defaultProvider.get();
+  }
+
+  /** Returns a declared provider provided by this target. Only meant to use from Skylark. */
+  @Nullable
+  @Override
+  public SkylarkClassObject get(ClassObjectConstructor.Key providerKey) {
+    if (providerKey.equals(DefaultProvider.SKYLARK_CONSTRUCTOR.getKey())) {
+      return getDefaultProvider();
+    }
+    SkylarkProviders skylarkProviders = getProvider(SkylarkProviders.class);
+    if (skylarkProviders != null) {
+      return skylarkProviders.getDeclaredProvider(providerKey);
+    }
+    return null;
+  }
 }