Add a DefaultBuildOptions specifying default build flags that may differ from the provided defaults in Options classes. These are used to create BuildOptionsDiffForReconstruction, which lets us store only the diffs in our BuildConfigurationValue.Keys.

PiperOrigin-RevId: 190117455

22 files changed, 359 insertions, 128 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
index ce726dcbed..deaddcbfa1 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
@@ -1062,7 +1062,9 @@ public class BuildView {
 
       @Override
       protected List<BuildConfiguration> getConfigurations(
-          FragmentClassSet fragments, Iterable<BuildOptions> buildOptions) {
+          FragmentClassSet fragments,
+          Iterable<BuildOptions> buildOptions,
+          BuildOptions defaultBuildOptions) {
         Preconditions.checkArgument(
             ct.getConfiguration().fragmentClasses().equals(fragments),
             "Mismatch: %s %s",
@@ -1091,7 +1093,8 @@ public class BuildView {
         getConfigurableAttributeKeysForTesting(eventHandler, ctgNode),
         toolchainContext == null
             ? ImmutableSet.of()
-            : toolchainContext.getResolvedToolchainLabels());
+            : toolchainContext.getResolvedToolchainLabels(),
+        skyframeExecutor.getDefaultBuildOptions());
   }
 
   /**
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java b/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java
index fb13cfb218..1edf561a50 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/ConfiguredTargetFactory.java
@@ -27,6 +27,7 @@ import com.google.devtools.build.lib.actions.FailAction;
 import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration.Fragment;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider;
 import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException;
 import com.google.devtools.build.lib.analysis.config.transitions.PatchTransition;
@@ -90,9 +91,12 @@ public final class ConfiguredTargetFactory {
   // in order to be accessible from the .view.skyframe package.
 
   private final ConfiguredRuleClassProvider ruleClassProvider;
+  private final BuildOptions defaultBuildOptions;
 
-  public ConfiguredTargetFactory(ConfiguredRuleClassProvider ruleClassProvider) {
+  public ConfiguredTargetFactory(
+      ConfiguredRuleClassProvider ruleClassProvider, BuildOptions defaultBuildOptions) {
     this.ruleClassProvider = ruleClassProvider;
+    this.defaultBuildOptions = defaultBuildOptions;
   }
 
   /**
@@ -174,7 +178,8 @@ public final class ConfiguredTargetFactory {
     ArtifactOwner owner =
         ConfiguredTargetKey.of(
             rule.getLabel(),
-            getArtifactOwnerConfiguration(analysisEnvironment.getSkyframeEnv(), configuration));
+            getArtifactOwnerConfiguration(
+                analysisEnvironment.getSkyframeEnv(), configuration, defaultBuildOptions));
     if (analysisEnvironment.getSkyframeEnv().valuesMissing()) {
       return null;
     }
@@ -190,11 +195,12 @@ public final class ConfiguredTargetFactory {
   }
 
   /**
-   * Returns the configuration's artifact owner (which may be null). Also returns null if the
-   * owning configuration isn't yet available from Skyframe.
+   * Returns the configuration's artifact owner (which may be null). Also returns null if the owning
+   * configuration isn't yet available from Skyframe.
    */
-  public static BuildConfiguration getArtifactOwnerConfiguration(SkyFunction.Environment env,
-      BuildConfiguration fromConfig) throws InterruptedException {
+  public static BuildConfiguration getArtifactOwnerConfiguration(
+      SkyFunction.Environment env, BuildConfiguration fromConfig, BuildOptions defaultBuildOptions)
+      throws InterruptedException {
     if (fromConfig == null) {
       return null;
     }
@@ -203,10 +209,14 @@ public final class ConfiguredTargetFactory {
       return fromConfig;
     }
     try {
-      BuildConfigurationValue ownerConfig = (BuildConfigurationValue) env.getValueOrThrow(
-          BuildConfigurationValue.key(
-              fromConfig.fragmentClasses(), ownerTransition.apply(fromConfig.getOptions())),
-          InvalidConfigurationException.class);
+      BuildConfigurationValue ownerConfig =
+          (BuildConfigurationValue)
+              env.getValueOrThrow(
+                  BuildConfigurationValue.key(
+                      fromConfig.fragmentClasses(),
+                      BuildOptions.diffForReconstruction(
+                          defaultBuildOptions, ownerTransition.apply(fromConfig.getOptions()))),
+                  InvalidConfigurationException.class);
       return ownerConfig == null ? null : ownerConfig.getConfiguration();
     } catch (InvalidConfigurationException e) {
       // We don't expect to have to handle an invalid configuration because in practice the owning
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/DependencyResolver.java b/src/main/java/com/google/devtools/build/lib/analysis/DependencyResolver.java
index 77fe0add2f..fbb23108ea 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/DependencyResolver.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/DependencyResolver.java
@@ -91,6 +91,8 @@ public abstract class DependencyResolver {
    * @param aspect the aspect applied to this target (if any)
    * @param configConditions resolver for config_setting labels
    * @param toolchainLabels required toolchain labels
+   * @param defaultBuildOptions default build options provided to the server to use for creating
+   *     diffs during key construction
    * @return a mapping of each attribute in this rule or aspects to its dependent nodes
    */
   public final OrderedSetMultimap<Attribute, Dependency> dependentNodeMap(
@@ -98,7 +100,8 @@ public abstract class DependencyResolver {
       BuildConfiguration hostConfig,
       @Nullable Aspect aspect,
       ImmutableMap<Label, ConfigMatchingProvider> configConditions,
-      ImmutableSet<Label> toolchainLabels)
+      ImmutableSet<Label> toolchainLabels,
+      BuildOptions defaultBuildOptions)
       throws EvalException, InvalidConfigurationException, InterruptedException,
           InconsistentAspectOrderException {
     NestedSetBuilder<Label> rootCauses = NestedSetBuilder.<Label>stableOrder();
@@ -109,7 +112,8 @@ public abstract class DependencyResolver {
             aspect != null ? ImmutableList.of(aspect) : ImmutableList.<Aspect>of(),
             configConditions,
             toolchainLabels,
-            rootCauses);
+            rootCauses,
+            defaultBuildOptions);
     if (!rootCauses.isEmpty()) {
       throw new IllegalStateException(rootCauses.build().iterator().next().toString());
     }
@@ -144,6 +148,8 @@ public abstract class DependencyResolver {
    * @param toolchainLabels required toolchain labels
    * @param rootCauses collector for dep labels that can't be (loading phase) loaded @return a
    *     mapping of each attribute in this rule or aspects to its dependent nodes
+   * @param defaultBuildOptions default build options provided by the server to use for creating
+   *     diffs during key construction
    */
   public final OrderedSetMultimap<Attribute, Dependency> dependentNodeMap(
       TargetAndConfiguration node,
@@ -151,7 +157,8 @@ public abstract class DependencyResolver {
       Iterable<Aspect> aspects,
       ImmutableMap<Label, ConfigMatchingProvider> configConditions,
       ImmutableSet<Label> toolchainLabels,
-      NestedSetBuilder<Label> rootCauses)
+      NestedSetBuilder<Label> rootCauses,
+      BuildOptions defaultBuildOptions)
       throws EvalException, InvalidConfigurationException, InterruptedException,
           InconsistentAspectOrderException {
     Target target = node.getTarget();
@@ -168,7 +175,14 @@ public abstract class DependencyResolver {
       visitTargetVisibility(node, rootCauses, outgoingEdges.get(null));
     } else if (target instanceof Rule) {
       visitRule(
-          node, hostConfig, aspects, configConditions, toolchainLabels, rootCauses, outgoingEdges);
+          node,
+          hostConfig,
+          aspects,
+          configConditions,
+          toolchainLabels,
+          rootCauses,
+          outgoingEdges,
+          defaultBuildOptions);
     } else if (target instanceof PackageGroup) {
       visitPackageGroup(node, (PackageGroup) target, rootCauses, outgoingEdges.get(null));
     } else {
@@ -185,7 +199,8 @@ public abstract class DependencyResolver {
       ImmutableMap<Label, ConfigMatchingProvider> configConditions,
       ImmutableSet<Label> toolchainLabels,
       NestedSetBuilder<Label> rootCauses,
-      OrderedSetMultimap<Attribute, Dependency> outgoingEdges)
+      OrderedSetMultimap<Attribute, Dependency> outgoingEdges,
+      BuildOptions defaultBuildOptions)
       throws EvalException, InvalidConfigurationException, InconsistentAspectOrderException,
           InterruptedException {
     Preconditions.checkArgument(node.getTarget() instanceof Rule);
@@ -199,7 +214,7 @@ public abstract class DependencyResolver {
 
     visitTargetVisibility(node, rootCauses, outgoingEdges.get(null));
     resolveEarlyBoundAttributes(depResolver);
-    resolveLateBoundAttributes(depResolver, ruleConfig, hostConfig);
+    resolveLateBoundAttributes(depResolver, ruleConfig, hostConfig, defaultBuildOptions);
 
     Attribute toolchainsAttribute =
         attributeMap.getAttributeDefinition(PlatformSemantics.TOOLCHAINS_ATTR);
@@ -330,34 +345,38 @@ public abstract class DependencyResolver {
   /**
    * Resolves the dependencies for all late-bound attributes in this rule.
    *
-   * <p>Late-bound attributes need special handling because they require configuration
-   * transitions to determine their values.
+   * <p>Late-bound attributes need special handling because they require configuration transitions
+   * to determine their values.
    *
    * <p>In other words, the normal process of dependency resolution is:
+   *
    * <ol>
-   *   <li>Find every label value in the rule's attributes</li>
+   *   <li>Find every label value in the rule's attributes
    *   <li>Apply configuration transitions over each value to get its dep configuration
-   *   <li>Return each value with its dep configuration</li>
+   *   <li>Return each value with its dep configuration
    * </ol>
    *
-   * This doesn't work for late-bound attributes because you can't get their values without
-   * knowing the configuration first. And that configuration may not be the owning rule's
-   * configuration. Specifically, {@link LateBoundDefault#useHostConfiguration()} switches to the
-   * host config and late-bound split attributes branch into multiple split configs.
+   * This doesn't work for late-bound attributes because you can't get their values without knowing
+   * the configuration first. And that configuration may not be the owning rule's configuration.
+   * Specifically, {@link LateBoundDefault#useHostConfiguration()} switches to the host config and
+   * late-bound split attributes branch into multiple split configs.
    *
-   * <p>This method implements that logic and makes sure the normal configuration
-   * transition logic mixes with it cleanly.
+   * <p>This method implements that logic and makes sure the normal configuration transition logic
+   * mixes with it cleanly.
    *
    * @param depResolver the resolver for this rule's deps
    * @param ruleConfig the rule's configuration
    * @param hostConfig the equivalent host configuration
+   * @param defaultBuildOptions default build options provided by the server to use for creating
+   *     diffs during key construction
    */
   private void resolveLateBoundAttributes(
       RuleResolver depResolver,
       BuildConfiguration ruleConfig,
-      BuildConfiguration hostConfig)
+      BuildConfiguration hostConfig,
+      BuildOptions defaultBuildOptions)
       throws EvalException, InvalidConfigurationException, InconsistentAspectOrderException,
-             InterruptedException{
+          InterruptedException {
     ConfiguredAttributeMapper attributeMap = depResolver.attributeMap;
     for (AttributeAndOwner attributeAndOwner : depResolver.attributes) {
       Attribute attribute = attributeAndOwner.attribute;
@@ -377,7 +396,7 @@ public abstract class DependencyResolver {
         // non-split branch, which calls TransitionResolver.evaluateTransition, which returns its
         // "host mode" result without ever looking at the split.
         Iterable<BuildConfiguration> splitConfigs =
-            getConfigurations(ruleConfig.fragmentClasses(), splitOptions);
+            getConfigurations(ruleConfig.fragmentClasses(), splitOptions, defaultBuildOptions);
         if (splitConfigs == null) {
           continue; // Need Skyframe deps.
         }
@@ -868,7 +887,9 @@ public abstract class DependencyResolver {
    */
   @Nullable
   protected abstract List<BuildConfiguration> getConfigurations(
-      FragmentClassSet fragments, Iterable<BuildOptions> buildOptions)
+      FragmentClassSet fragments,
+      Iterable<BuildOptions> buildOptions,
+      BuildOptions defaultBuildOptions)
       throws InvalidConfigurationException, InterruptedException;
 
   /**
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
index 9f5c6263b5..4308cd4f1c 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildConfiguration.java
@@ -1171,6 +1171,7 @@ public class BuildConfiguration {
   private final ActionEnvironment testEnv;
 
   private final BuildOptions buildOptions;
+  private final BuildOptions.OptionsDiffForReconstruction buildOptionsDiff;
   private final Options options;
 
   private final String mnemonic;
@@ -1323,12 +1324,12 @@ public class BuildConfiguration {
     return fragmentsInterner.intern(ImmutableSortedMap.copyOf(fragmentsMap, lexicalFragmentSorter));
   }
 
-  /**
-   * Constructs a new BuildConfiguration instance.
-   */
-  public BuildConfiguration(BlazeDirectories directories,
+  /** Constructs a new BuildConfiguration instance. */
+  public BuildConfiguration(
+      BlazeDirectories directories,
       Map<Class<? extends Fragment>, Fragment> fragmentsMap,
       BuildOptions buildOptions,
+      BuildOptions.OptionsDiffForReconstruction buildOptionsDiff,
       String repositoryName) {
     this.directories = directories;
     this.fragments = makeFragmentsMap(fragmentsMap);
@@ -1337,6 +1338,7 @@ public class BuildConfiguration {
     this.skylarkVisibleFragments = buildIndexOfSkylarkVisibleFragments();
     this.repositoryName = repositoryName;
     this.buildOptions = buildOptions.clone();
+    this.buildOptionsDiff = buildOptionsDiff;
     this.actionsEnabled = buildOptions.enableActions();
     this.options = buildOptions.get(Options.class);
     this.separateGenfilesDirectory = options.separateGenfilesDirectory;
@@ -1419,7 +1421,9 @@ public class BuildConfiguration {
    * configuration is assumed to have).
    */
   public BuildConfiguration clone(
-      FragmentClassSet fragmentClasses, RuleClassProvider ruleClassProvider) {
+      FragmentClassSet fragmentClasses,
+      RuleClassProvider ruleClassProvider,
+      BuildOptions defaultBuildOptions) {
 
     ClassToInstanceMap<Fragment> fragmentsMap = MutableClassToInstanceMap.create();
     for (Fragment fragment : fragments.values()) {
@@ -1434,6 +1438,7 @@ public class BuildConfiguration {
             directories,
             fragmentsMap,
             options,
+            BuildOptions.diffForReconstruction(defaultBuildOptions, options),
             mainRepositoryName.strippedName());
     return newConfig;
   }
@@ -1962,6 +1967,10 @@ public class BuildConfiguration {
     return buildOptions;
   }
 
+  public BuildOptions.OptionsDiffForReconstruction getBuildOptionsDiff() {
+    return buildOptionsDiff;
+  }
+
   public String getCpu() {
     return options.cpu;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildOptions.java b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildOptions.java
index ddfdc560ea..c4ce4e5ea3 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/config/BuildOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/config/BuildOptions.java
@@ -291,10 +291,14 @@ public final class BuildOptions implements Cloneable, Serializable {
     this.fragmentOptionsMap = fragmentOptionsMap;
   }
 
-  BuildOptions applyDiff(OptionsDiffForReconstruction optionsDiff) {
+  public BuildOptions applyDiff(OptionsDiffForReconstruction optionsDiff) {
     if (optionsDiff.isEmpty()) {
       return this;
     }
+    maybeInitializeFingerprintAndHashCode();
+    if (!Arrays.equals(fingerprint, optionsDiff.baseFingerprint)) {
+      throw new IllegalArgumentException("Can not reconstruct BuildOptions with a different base.");
+    }
     Builder builder = builder();
     for (FragmentOptions options : fragmentOptionsMap.values()) {
       FragmentOptions newOptions = optionsDiff.transformOptions(options);
@@ -342,6 +346,9 @@ public final class BuildOptions implements Cloneable, Serializable {
 
   /** Returns the difference between two BuildOptions in a {@link BuildOptions.OptionsDiff}. */
   public static OptionsDiff diff(BuildOptions first, BuildOptions second) {
+    if (first == null || second == null) {
+      throw new IllegalArgumentException("Cannot diff null BuildOptions");
+    }
     OptionsDiff diff = new OptionsDiff();
     if (first.equals(second)) {
       return diff;
@@ -390,25 +397,25 @@ public final class BuildOptions implements Cloneable, Serializable {
       BuildOptions first, BuildOptions second) {
     OptionsDiff diff = diff(first, second);
     if (diff.areSame()) {
-      return OptionsDiffForReconstruction.EMPTY;
+      return OptionsDiffForReconstruction.getEmpty(first.fingerprint);
     }
-    ImmutableMap.Builder<Class<? extends FragmentOptions>, ImmutableMap<String, Object>>
-        differingOptionsBuilder =
-            ImmutableMap.builderWithExpectedSize(diff.differingOptions.keySet().size());
+    HashMap<Class<? extends FragmentOptions>, Map<String, Object>> differingOptions =
+        new HashMap<>(diff.differingOptions.keySet().size());
     for (Class<? extends FragmentOptions> clazz : diff.differingOptions.keySet()) {
       Collection<OptionDefinition> fields = diff.differingOptions.get(clazz);
-      ImmutableMap.Builder<String, Object> valuesMapBuilder =
-          ImmutableMap.builderWithExpectedSize(fields.size());
+      HashMap<String, Object> valueMap = new HashMap<>(fields.size());
       for (OptionDefinition optionDefinition : fields) {
-        valuesMapBuilder.put(
-            optionDefinition.getField().getName(), diff.second.get(optionDefinition));
+        Object secondValue = diff.second.get(optionDefinition);
+        valueMap.put(optionDefinition.getField().getName(), secondValue);
       }
-      differingOptionsBuilder.put(clazz, valuesMapBuilder.build());
+      differingOptions.put(clazz, valueMap);
     }
+    first.maybeInitializeFingerprintAndHashCode();
     return new OptionsDiffForReconstruction(
-        differingOptionsBuilder.build(),
+        differingOptions,
         ImmutableSet.copyOf(diff.extraFirstFragments),
-        ImmutableList.copyOf(diff.extraSecondFragments));
+        ImmutableList.copyOf(diff.extraSecondFragments),
+        first.fingerprint);
   }
 
   /**
@@ -492,35 +499,38 @@ public final class BuildOptions implements Cloneable, Serializable {
    * omitted, and the values of any fields that should be changed.
    */
   @AutoCodec
-  static class OptionsDiffForReconstruction {
-    @AutoCodec
-    static final OptionsDiffForReconstruction EMPTY =
-        new OptionsDiffForReconstruction(ImmutableMap.of(), ImmutableSet.of(), ImmutableList.of());
-
-    private final ImmutableMap<Class<? extends FragmentOptions>, ImmutableMap<String, Object>>
-        differingOptions;
+  public static class OptionsDiffForReconstruction {
+    private final Map<Class<? extends FragmentOptions>, Map<String, Object>> differingOptions;
     private final ImmutableSet<Class<? extends FragmentOptions>> extraFirstFragmentClasses;
     private final ImmutableList<FragmentOptions> extraSecondFragments;
+    private final byte[] baseFingerprint;
 
     @AutoCodec.VisibleForSerialization
     OptionsDiffForReconstruction(
-        ImmutableMap<Class<? extends FragmentOptions>, ImmutableMap<String, Object>>
-            differingOptions,
+        Map<Class<? extends FragmentOptions>, Map<String, Object>> differingOptions,
         ImmutableSet<Class<? extends FragmentOptions>> extraFirstFragmentClasses,
-        ImmutableList<FragmentOptions> extraSecondFragments) {
+        ImmutableList<FragmentOptions> extraSecondFragments,
+        byte[] baseFingerprint) {
       this.differingOptions = differingOptions;
       this.extraFirstFragmentClasses = extraFirstFragmentClasses;
       this.extraSecondFragments = extraSecondFragments;
+      this.baseFingerprint = baseFingerprint;
+    }
+
+    private static OptionsDiffForReconstruction getEmpty(byte[] baseFingerprint) {
+      return new OptionsDiffForReconstruction(
+          ImmutableMap.of(), ImmutableSet.of(), ImmutableList.of(), baseFingerprint);
     }
 
     @Nullable
-    private FragmentOptions transformOptions(FragmentOptions input) {
+    @VisibleForTesting
+    FragmentOptions transformOptions(FragmentOptions input) {
       Class<? extends FragmentOptions> clazz = input.getClass();
       if (extraFirstFragmentClasses.contains(clazz)) {
         return null;
       }
       Map<String, Object> changedOptions = differingOptions.get(clazz);
-      if (changedOptions.isEmpty()) {
+      if (changedOptions == null || changedOptions.isEmpty()) {
         return input;
       }
       FragmentOptions newOptions = input.clone();
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigurationResolver.java b/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigurationResolver.java
index e67ea1e6c9..862bdbeade 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigurationResolver.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/config/ConfigurationResolver.java
@@ -94,7 +94,6 @@ public final class ConfigurationResolver {
    * @param originalDeps the transition requests for each dep under this target's attributes
    * @param hostConfiguration the host configuration
    * @param ruleClassProvider provider for determining the right configuration fragments for deps
-   *
    * @return a mapping from each attribute in the source target to the {@link BuildConfiguration}s
    *     and {@link Label}s for the deps under that attribute. Returns null if not all Skyframe
    *     dependencies are available.
@@ -105,7 +104,8 @@ public final class ConfigurationResolver {
       TargetAndConfiguration ctgValue,
       OrderedSetMultimap<Attribute, Dependency> originalDeps,
       BuildConfiguration hostConfiguration,
-      RuleClassProvider ruleClassProvider)
+      RuleClassProvider ruleClassProvider,
+      BuildOptions defaultBuildOptions)
       throws ConfiguredTargetFunction.DependencyEvaluationException, InterruptedException {
 
     // Maps each Skyframe-evaluated BuildConfiguration to the dependencies that need that
@@ -232,10 +232,16 @@ public final class ConfigurationResolver {
       // If we get here, we have to get the configuration from Skyframe.
       for (BuildOptions options : toOptions) {
         if (sameFragments) {
-          keysToEntries.put(BuildConfigurationValue.key(ctgFragments, options), depsEntry);
+          keysToEntries.put(
+              BuildConfigurationValue.key(
+                  ctgFragments, BuildOptions.diffForReconstruction(defaultBuildOptions, options)),
+              depsEntry);
 
         } else {
-          keysToEntries.put(BuildConfigurationValue.key(depFragments, options), depsEntry);
+          keysToEntries.put(
+              BuildConfigurationValue.key(
+                  depFragments, BuildOptions.diffForReconstruction(defaultBuildOptions, options)),
+              depsEntry);
         }
       }
     }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
index ade1c0fc30..8594e6339c 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java
@@ -16,6 +16,7 @@ package com.google.devtools.build.lib.bazel.rules;
 
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.bazel.rules.cpp.BazelCppRuleClasses;
 import com.google.devtools.build.lib.rules.cpp.FdoSupportFunction;
 import com.google.devtools.build.lib.rules.cpp.FdoSupportValue;
@@ -50,4 +51,10 @@ public class BazelRulesModule extends BlazeModule {
       BlazeRuntime runtime, BlazeDirectories directories, WorkspaceBuilder builder) {
     builder.addSkyFunction(FdoSupportValue.SKYFUNCTION, new FdoSupportFunction(directories));
   }
+
+  @Override
+  public BuildOptions getDefaultBuildOptions(BlazeRuntime blazeRuntime) {
+    return DefaultBuildOptionsForDiffing.getDefaultBuildOptionsForFragments(
+        blazeRuntime.getRuleClassProvider().getConfigurationOptions());
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/DefaultBuildOptionsForDiffing.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/DefaultBuildOptionsForDiffing.java
new file mode 100644
index 0000000000..7e7a39f678
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/DefaultBuildOptionsForDiffing.java
@@ -0,0 +1,50 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.bazel.rules;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
+import com.google.devtools.build.lib.analysis.config.FragmentOptions;
+import com.google.devtools.common.options.OptionsParsingException;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Provides default {@link BuildOptions} based on the Fragment Classes provided. These default
+ * BuildOptions are used to create {@link BuildOptions.OptionsDiffForReconstruction} to store in
+ * {@link BuildConfigurationValue.Key}.
+ */
+public class DefaultBuildOptionsForDiffing {
+
+  private static final ImmutableMap<Class<? extends FragmentOptions>, List<String>>
+      DEFAULT_OPTIONS_MAP = ImmutableMap.of();
+
+  public static BuildOptions getDefaultBuildOptionsForFragments(
+      List<Class<? extends FragmentOptions>> fragmentClasses) {
+    ArrayList<String> collector = new ArrayList<>();
+    for (Class<? extends FragmentOptions> clazz : fragmentClasses) {
+      List<String> options = DEFAULT_OPTIONS_MAP.get(clazz);
+      if (options != null) {
+        collector.addAll(options);
+      }
+    }
+    try {
+      String[] stringCollector = new String[collector.size()];
+      return BuildOptions.of(fragmentClasses, collector.toArray(stringCollector));
+    } catch (OptionsParsingException e) {
+      throw new IllegalArgumentException("Failed to parse default options", e);
+    }
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeModule.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeModule.java
index 4eb1908598..df96bb72f6 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeModule.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeModule.java
@@ -18,6 +18,7 @@ import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.BlazeVersionInfo;
 import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
 import com.google.devtools.build.lib.analysis.ServerDirectories;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.test.CoverageReportActionFactory;
 import com.google.devtools.build.lib.buildtool.BuildRequest;
 import com.google.devtools.build.lib.clock.Clock;
@@ -213,6 +214,15 @@ public abstract class BlazeModule {
   }
 
   /**
+   * Returns an instance of BuildOptions to be used to create {@link
+   * BuildOptions.OptionsDiffForReconstruction} with. Only one installed Module should override
+   * this.
+   */
+  public BuildOptions getDefaultBuildOptions(BlazeRuntime runtime) {
+    return null;
+  }
+
+  /**
    * Called when Bazel initializes the action execution subsystem. This is called once per build if
    * action execution is enabled. Modules can override this method to affect how execution is
    * performed.
@@ -221,8 +231,7 @@ public abstract class BlazeModule {
    * @param request the build request
    * @param builder the builder to add action context providers and consumers to
    */
-  public void executorInit(CommandEnvironment env, BuildRequest request, ExecutorBuilder builder) {
-  }
+  public void executorInit(CommandEnvironment env, BuildRequest request, ExecutorBuilder builder) {}
 
   /**
    * Called after each command.
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
index 6e04c6170d..09467f1478 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
@@ -354,6 +354,25 @@ public final class BlazeRuntime {
     return blazeModules;
   }
 
+  public BuildOptions getDefaultBuildOptions() {
+    BuildOptions options = null;
+    for (BlazeModule module : blazeModules) {
+      BuildOptions optionsFromModule = module.getDefaultBuildOptions(this);
+      if (optionsFromModule != null) {
+        if (options == null) {
+          options = optionsFromModule;
+        } else {
+          throw new IllegalArgumentException(
+              "Two or more blaze modules contained default build options.");
+        }
+      }
+    }
+    if (options == null) {
+      throw new IllegalArgumentException("No default build options specified in any Blaze module");
+    }
+    return options;
+  }
+
   @SuppressWarnings("unchecked")
   public <T extends BlazeModule> T getBlazeModule(Class<T> moduleClass) {
     for (BlazeModule module : blazeModules) {
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/WorkspaceBuilder.java b/src/main/java/com/google/devtools/build/lib/runtime/WorkspaceBuilder.java
index 7e86341316..1e9ee5c7ac 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/WorkspaceBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/WorkspaceBuilder.java
@@ -65,7 +65,8 @@ public final class WorkspaceBuilder {
       SubscriberExceptionHandler eventBusExceptionHandler) throws AbruptExitException {
     // Set default values if none are set.
     if (skyframeExecutorFactory == null) {
-      skyframeExecutorFactory = new SequencedSkyframeExecutorFactory();
+      skyframeExecutorFactory =
+          new SequencedSkyframeExecutorFactory(runtime.getDefaultBuildOptions());
     }
 
     SkyframeExecutor skyframeExecutor =
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
index 917dfcb9dd..37ca17c17f 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
@@ -32,6 +32,7 @@ import com.google.devtools.build.lib.analysis.DependencyResolver.InconsistentAsp
 import com.google.devtools.build.lib.analysis.TargetAndConfiguration;
 import com.google.devtools.build.lib.analysis.ToolchainContext;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider;
 import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException;
 import com.google.devtools.build.lib.analysis.configuredtargets.MergedConfiguredTarget;
@@ -97,6 +98,7 @@ public final class AspectFunction implements SkyFunction {
   private final BuildViewProvider buildViewProvider;
   private final RuleClassProvider ruleClassProvider;
   private final Supplier<Boolean> removeActionsAfterEvaluation;
+  private final BuildOptions defaultBuildOptions;
   /**
    * Indicates whether the set of packages transitively loaded for a given {@link AspectValue} will
    * be needed for package root resolution later in the build. If not, they are not collected and
@@ -108,12 +110,14 @@ public final class AspectFunction implements SkyFunction {
       BuildViewProvider buildViewProvider,
       RuleClassProvider ruleClassProvider,
       Supplier<Boolean> removeActionsAfterEvaluation,
-      boolean storeTransitivePackagesForPackageRootResolution) {
+      boolean storeTransitivePackagesForPackageRootResolution,
+      BuildOptions defaultBuildOptions) {
     this.buildViewProvider = buildViewProvider;
     this.ruleClassProvider = ruleClassProvider;
     this.removeActionsAfterEvaluation = Preconditions.checkNotNull(removeActionsAfterEvaluation);
     this.storeTransitivePackagesForPackageRootResolution =
         storeTransitivePackagesForPackageRootResolution;
+    this.defaultBuildOptions = defaultBuildOptions;
   }
 
   /**
@@ -382,7 +386,8 @@ public final class AspectFunction implements SkyFunction {
                 ruleClassProvider,
                 view.getHostConfiguration(originalTargetAndAspectConfiguration.getConfiguration()),
                 transitivePackagesForPackageRootResolution,
-                transitiveRootCauses);
+                transitiveRootCauses,
+                defaultBuildOptions);
       } catch (ConfiguredTargetFunctionException e) {
         throw new AspectCreationException(e.getMessage());
       }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationFunction.java
index e335ceaa71..6b39f2883b 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationFunction.java
@@ -21,6 +21,7 @@ import com.google.common.collect.MutableClassToInstanceMap;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException;
 import com.google.devtools.build.lib.packages.RuleClassProvider;
 import com.google.devtools.build.skyframe.SkyFunction;
@@ -39,11 +40,15 @@ public class BuildConfigurationFunction implements SkyFunction {
 
   private final BlazeDirectories directories;
   private final ConfiguredRuleClassProvider ruleClassProvider;
+  private final BuildOptions defaultBuildOptions;
 
-  public BuildConfigurationFunction(BlazeDirectories directories,
-      RuleClassProvider ruleClassProvider) {
+  public BuildConfigurationFunction(
+      BlazeDirectories directories,
+      RuleClassProvider ruleClassProvider,
+      BuildOptions defaultBuildOptions) {
     this.directories = directories;
     this.ruleClassProvider = (ConfiguredRuleClassProvider) ruleClassProvider;
+    this.defaultBuildOptions = defaultBuildOptions;
   }
 
   @Override
@@ -71,12 +76,11 @@ public class BuildConfigurationFunction implements SkyFunction {
       fragmentsMap.put(fragment.getClass(), fragment);
     }
 
+    BuildOptions options = defaultBuildOptions.applyDiff(key.getOptionsDiff());
+
     BuildConfiguration config =
         new BuildConfiguration(
-            directories,
-            fragmentsMap,
-            key.getBuildOptions(),
-            workspaceNameValue.getName());
+            directories, fragmentsMap, options, key.getOptionsDiff(), workspaceNameValue.getName());
     return new BuildConfigurationValue(config);
   }
 
@@ -85,9 +89,9 @@ public class BuildConfigurationFunction implements SkyFunction {
 
     // Get SkyKeys for the fragments we need to load.
     Set<SkyKey> fragmentKeys = new LinkedHashSet<>();
+    BuildOptions options = defaultBuildOptions.applyDiff(key.getOptionsDiff());
     for (Class<? extends BuildConfiguration.Fragment> fragmentClass : key.getFragments()) {
-      fragmentKeys.add(
-          ConfigurationFragmentValue.key(key.getBuildOptions(), fragmentClass, ruleClassProvider));
+      fragmentKeys.add(ConfigurationFragmentValue.key(options, fragmentClass, ruleClassProvider));
     }
 
     // Load them as Skyframe deps.
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationValue.java
index b445cc0a2b..8eed98ce64 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/BuildConfigurationValue.java
@@ -13,7 +13,6 @@
 // limitations under the License.
 package com.google.devtools.build.lib.skyframe;
 
-import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSortedSet;
 import com.google.common.collect.Interner;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
@@ -44,7 +43,6 @@ import java.util.Set;
 @AutoCodec
 @ThreadSafe
 public class BuildConfigurationValue implements SkyValue {
-  private static final Interner<Key> keyInterner = BlazeInterners.newWeakInterner();
 
   private final BuildConfiguration configuration;
 
@@ -60,40 +58,50 @@ public class BuildConfigurationValue implements SkyValue {
    * Returns the key for a requested configuration.
    *
    * @param fragments the fragments the configuration should contain
-   * @param buildOptions the build options the fragments should be built from
+   * @param optionsDiff the {@link BuildOptions.OptionsDiffForReconstruction} object the {@link
+   *     BuildOptions} should be rebuilt from
    */
   @ThreadSafe
   public static Key key(
-      Set<Class<? extends BuildConfiguration.Fragment>> fragments, BuildOptions buildOptions) {
+      Set<Class<? extends BuildConfiguration.Fragment>> fragments,
+      BuildOptions.OptionsDiffForReconstruction optionsDiff) {
     return key(
         FragmentClassSet.of(
             ImmutableSortedSet.copyOf(BuildConfiguration.lexicalFragmentSorter, fragments)),
-        buildOptions);
+        optionsDiff);
   }
 
-  public static Key key(FragmentClassSet fragmentClassSet, BuildOptions buildOptions) {
-    return keyInterner.intern(new Key(fragmentClassSet, buildOptions));
+  public static Key key(
+      FragmentClassSet fragmentClassSet, BuildOptions.OptionsDiffForReconstruction optionsDiff) {
+    return Key.create(fragmentClassSet, optionsDiff);
   }
 
   /** {@link SkyKey} for {@link BuildConfigurationValue}. */
   @VisibleForSerialization
   public static final class Key implements SkyKey, Serializable {
+    private static final Interner<Key> keyInterner = BlazeInterners.newWeakInterner();
+
     private final FragmentClassSet fragments;
-    private final BuildOptions buildOptions;
+    private final BuildOptions.OptionsDiffForReconstruction optionsDiff;
     // If hashCode really is -1, we'll recompute it from scratch each time. Oh well.
     private volatile int hashCode = -1;
 
-    private Key(FragmentClassSet fragments, BuildOptions buildOptions) {
+    private static Key create(
+        FragmentClassSet fragments, BuildOptions.OptionsDiffForReconstruction optionsDiff) {
+      return keyInterner.intern(new Key(fragments, optionsDiff));
+    }
+
+    Key(FragmentClassSet fragments, BuildOptions.OptionsDiffForReconstruction optionsDiff) {
       this.fragments = fragments;
-      this.buildOptions = Preconditions.checkNotNull(buildOptions);
+      this.optionsDiff = optionsDiff;
     }
 
     ImmutableSortedSet<Class<? extends BuildConfiguration.Fragment>> getFragments() {
       return fragments.fragmentClasses();
     }
 
-    BuildOptions getBuildOptions() {
-      return buildOptions;
+    BuildOptions.OptionsDiffForReconstruction getOptionsDiff() {
+      return optionsDiff;
     }
 
     @Override
@@ -110,14 +118,14 @@ public class BuildConfigurationValue implements SkyValue {
         return false;
       }
       Key otherConfig = (Key) o;
-      return buildOptions.equals(otherConfig.buildOptions)
+      return optionsDiff.equals(otherConfig.optionsDiff)
           && Objects.equals(fragments, otherConfig.fragments);
     }
 
     @Override
     public int hashCode() {
       if (hashCode == -1) {
-        hashCode = Objects.hash(fragments, buildOptions);
+        hashCode = Objects.hash(fragments, optionsDiff);
       }
       return hashCode;
     }
@@ -131,7 +139,7 @@ public class BuildConfigurationValue implements SkyValue {
       @Override
       public void serialize(SerializationContext context, Key obj, CodedOutputStream codedOut)
           throws SerializationException, IOException {
-        context.serialize(obj.buildOptions, codedOut);
+        context.serialize(obj.optionsDiff, codedOut);
         codedOut.writeInt32NoTag(obj.fragments.fragmentClasses().size());
         for (Class<? extends BuildConfiguration.Fragment> fragment :
             obj.fragments.fragmentClasses()) {
@@ -143,7 +151,7 @@ public class BuildConfigurationValue implements SkyValue {
       @SuppressWarnings("unchecked") // Class<? extends...> cast
       public Key deserialize(DeserializationContext context, CodedInputStream codedIn)
           throws SerializationException, IOException {
-        BuildOptions buildOptions = context.deserialize(codedIn);
+        BuildOptions.OptionsDiffForReconstruction optionsDiff = context.deserialize(codedIn);
         int fragmentsSize = codedIn.readInt32();
         ImmutableSortedSet.Builder<Class<? extends BuildConfiguration.Fragment>> fragmentsBuilder =
             ImmutableSortedSet.orderedBy(BuildConfiguration.lexicalFragmentSorter);
@@ -157,7 +165,7 @@ public class BuildConfigurationValue implements SkyValue {
                 "Couldn't deserialize BuildConfigurationValue$Key fragment class", e);
           }
         }
-        return key(fragmentsBuilder.build(), buildOptions);
+        return key(fragmentsBuilder.build(), optionsDiff);
       }
     }
   }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
index 2df73d1791..a4bb22fce0 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
@@ -33,6 +33,7 @@ import com.google.devtools.build.lib.analysis.DependencyResolver.InconsistentAsp
 import com.google.devtools.build.lib.analysis.TargetAndConfiguration;
 import com.google.devtools.build.lib.analysis.ToolchainContext;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider;
 import com.google.devtools.build.lib.analysis.config.ConfigurationResolver;
 import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException;
@@ -116,6 +117,7 @@ public final class ConfiguredTargetFunction implements SkyFunction {
   private final RuleClassProvider ruleClassProvider;
   private final Semaphore cpuBoundSemaphore;
   private final Supplier<Boolean> removeActionsAfterEvaluation;
+  private final BuildOptions defaultBuildOptions;
   /**
    * Indicates whether the set of packages transitively loaded for a given {@link
    * ConfiguredTargetValue} will be needed for package root resolution later in the build. If not,
@@ -128,13 +130,15 @@ public final class ConfiguredTargetFunction implements SkyFunction {
       RuleClassProvider ruleClassProvider,
       Semaphore cpuBoundSemaphore,
       Supplier<Boolean> removeActionsAfterEvaluation,
-      boolean storeTransitivePackagesForPackageRootResolution) {
+      boolean storeTransitivePackagesForPackageRootResolution,
+      BuildOptions defaultBuildOptions) {
     this.buildViewProvider = buildViewProvider;
     this.ruleClassProvider = ruleClassProvider;
     this.cpuBoundSemaphore = cpuBoundSemaphore;
     this.removeActionsAfterEvaluation = Preconditions.checkNotNull(removeActionsAfterEvaluation);
     this.storeTransitivePackagesForPackageRootResolution =
         storeTransitivePackagesForPackageRootResolution;
+    this.defaultBuildOptions = defaultBuildOptions;
   }
 
   @Override
@@ -269,7 +273,8 @@ public final class ConfiguredTargetFunction implements SkyFunction {
               ruleClassProvider,
               view.getHostConfiguration(configuration),
               transitivePackagesForPackageRootResolution,
-              transitiveLoadingRootCauses);
+              transitiveLoadingRootCauses,
+              defaultBuildOptions);
       if (env.valuesMissing()) {
         return null;
       }
@@ -380,6 +385,9 @@ public final class ConfiguredTargetFunction implements SkyFunction {
    * @param hostConfiguration the host configuration. There's a noticeable performance hit from
    *     instantiating this on demand for every dependency that wants it, so it's best to compute
    *     the host configuration as early as possible and pass this reference to all consumers
+   * @param defaultBuildOptions the default build options provided by the server; these are used to
+   *     create diffs for {@link BuildConfigurationValue.Key}s to prevent storing the entire
+   *     BuildOptions object.
    */
   @Nullable
   static OrderedSetMultimap<Attribute, ConfiguredTargetAndData> computeDependencies(
@@ -392,7 +400,8 @@ public final class ConfiguredTargetFunction implements SkyFunction {
       RuleClassProvider ruleClassProvider,
       BuildConfiguration hostConfiguration,
       @Nullable NestedSetBuilder<Package> transitivePackagesForPackageRootResolution,
-      NestedSetBuilder<Label> transitiveLoadingRootCauses)
+      NestedSetBuilder<Label> transitiveLoadingRootCauses,
+      BuildOptions defaultBuildOptions)
       throws DependencyEvaluationException, ConfiguredTargetFunctionException,
           AspectCreationException, InterruptedException {
     // Create the map from attributes to set of (target, configuration) pairs.
@@ -407,7 +416,8 @@ public final class ConfiguredTargetFunction implements SkyFunction {
               toolchainContext == null
                   ? ImmutableSet.of()
                   : toolchainContext.getResolvedToolchainLabels(),
-              transitiveLoadingRootCauses);
+              transitiveLoadingRootCauses,
+              defaultBuildOptions);
     } catch (EvalException e) {
       // EvalException can only be thrown by computed Skylark attributes in the current rule.
       env.getListener().handle(Event.error(e.getLocation(), e.getMessage()));
@@ -423,8 +433,14 @@ public final class ConfiguredTargetFunction implements SkyFunction {
     // Trim each dep's configuration so it only includes the fragments needed by its transitive
     // closure.
     if (ctgValue.getConfiguration() != null) {
-      depValueNames = ConfigurationResolver.resolveConfigurations(env, ctgValue, depValueNames,
-          hostConfiguration, ruleClassProvider);
+      depValueNames =
+          ConfigurationResolver.resolveConfigurations(
+              env,
+              ctgValue,
+              depValueNames,
+              hostConfiguration,
+              ruleClassProvider,
+              defaultBuildOptions);
       // It's important that we don't use "if (env.missingValues()) { return null }" here (or
       // in the following lines). See the comments in getDynamicConfigurations' Skyframe call
       // for explanation.
@@ -686,7 +702,8 @@ public final class ConfiguredTargetFunction implements SkyFunction {
       throws ConfiguredTargetFunctionException, InterruptedException {
     StoredEventHandler events = new StoredEventHandler();
     BuildConfiguration ownerConfig =
-        ConfiguredTargetFactory.getArtifactOwnerConfiguration(env, configuration);
+        ConfiguredTargetFactory.getArtifactOwnerConfiguration(
+            env, configuration, defaultBuildOptions);
     if (env.valuesMissing()) {
       return null;
     }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetKey.java b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetKey.java
index f9489794cc..e5692d3376 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetKey.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetKey.java
@@ -80,7 +80,7 @@ public class ConfiguredTargetKey extends ActionLookupKey {
         ? KeyAndHost.NULL_INSTANCE
         : new KeyAndHost(
             BuildConfigurationValue.key(
-                configuration.fragmentClasses(), configuration.getOptions()),
+                configuration.fragmentClasses(), configuration.getBuildOptionsDiff()),
             configuration.isHostConfiguration());
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PostConfiguredTargetFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/PostConfiguredTargetFunction.java
index c8e61fe10a..2a35b9f186 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PostConfiguredTargetFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PostConfiguredTargetFunction.java
@@ -24,6 +24,7 @@ import com.google.devtools.build.lib.analysis.Dependency;
 import com.google.devtools.build.lib.analysis.DependencyResolver.InconsistentAspectOrderException;
 import com.google.devtools.build.lib.analysis.TargetAndConfiguration;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.ConfigMatchingProvider;
 import com.google.devtools.build.lib.analysis.config.ConfigurationResolver;
 import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException;
@@ -64,12 +65,15 @@ public class PostConfiguredTargetFunction implements SkyFunction {
 
   private final SkyframeExecutor.BuildViewProvider buildViewProvider;
   private final RuleClassProvider ruleClassProvider;
+  private final BuildOptions defaultBuildOptions;
 
   public PostConfiguredTargetFunction(
       SkyframeExecutor.BuildViewProvider buildViewProvider,
-      RuleClassProvider ruleClassProvider) {
+      RuleClassProvider ruleClassProvider,
+      BuildOptions defaultBuildOptions) {
     this.buildViewProvider = Preconditions.checkNotNull(buildViewProvider);
     this.ruleClassProvider = ruleClassProvider;
+    this.defaultBuildOptions = defaultBuildOptions;
   }
 
   @Nullable
@@ -125,10 +129,12 @@ public class PostConfiguredTargetFunction implements SkyFunction {
               hostConfiguration,
               /*aspect=*/ null,
               configConditions,
-              /*toolchainLabels=*/ ImmutableSet.of());
+              /*toolchainLabels*/ ImmutableSet.of(),
+              defaultBuildOptions);
       if (ct.getConfiguration() != null) {
-        deps = ConfigurationResolver.resolveConfigurations(env, ctgValue, deps, hostConfiguration,
-            ruleClassProvider);
+        deps =
+            ConfigurationResolver.resolveConfigurations(
+                env, ctgValue, deps, hostConfiguration, ruleClassProvider, defaultBuildOptions);
       }
     } catch (EvalException | ConfiguredTargetFunction.DependencyEvaluationException
         | InvalidConfigurationException | InconsistentAspectOrderException e) {
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutor.java
index 88cced7588..3c25ef34d6 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutor.java
@@ -34,6 +34,7 @@ import com.google.devtools.build.lib.analysis.BuildView;
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
 import com.google.devtools.build.lib.analysis.WorkspaceStatusAction.Factory;
 import com.google.devtools.build.lib.analysis.buildinfo.BuildInfoFactory;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.configuredtargets.RuleConfiguredTarget;
 import com.google.devtools.build.lib.buildtool.BuildRequestOptions;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
@@ -147,7 +148,8 @@ public final class SequencedSkyframeExecutor extends SkyframeExecutor {
       PathFragment additionalBlacklistedPackagePrefixesFile,
       CrossRepositoryLabelViolationStrategy crossRepositoryLabelViolationStrategy,
       List<BuildFileName> buildFilesByPriority,
-      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile) {
+      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile,
+      BuildOptions defaultBuildOptions) {
     super(
         evaluatorSupplier,
         pkgFactory,
@@ -162,7 +164,8 @@ public final class SequencedSkyframeExecutor extends SkyframeExecutor {
         additionalBlacklistedPackagePrefixesFile,
         crossRepositoryLabelViolationStrategy,
         buildFilesByPriority,
-        actionOnIOExceptionReadingBuildFile);
+        actionOnIOExceptionReadingBuildFile,
+        defaultBuildOptions);
     this.diffAwarenessManager = new DiffAwarenessManager(diffAwarenessFactories);
     this.customDirtinessCheckers = customDirtinessCheckers;
   }
@@ -181,7 +184,8 @@ public final class SequencedSkyframeExecutor extends SkyframeExecutor {
       PathFragment additionalBlacklistedPackagePrefixesFile,
       CrossRepositoryLabelViolationStrategy crossRepositoryLabelViolationStrategy,
       List<BuildFileName> buildFilesByPriority,
-      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile) {
+      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile,
+      BuildOptions defaultBuildOptions) {
     SequencedSkyframeExecutor skyframeExecutor =
         new SequencedSkyframeExecutor(
             InMemoryMemoizingEvaluator.SUPPLIER,
@@ -198,7 +202,8 @@ public final class SequencedSkyframeExecutor extends SkyframeExecutor {
             additionalBlacklistedPackagePrefixesFile,
             crossRepositoryLabelViolationStrategy,
             buildFilesByPriority,
-            actionOnIOExceptionReadingBuildFile);
+            actionOnIOExceptionReadingBuildFile,
+            defaultBuildOptions);
     skyframeExecutor.init();
     return skyframeExecutor;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutorFactory.java b/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutorFactory.java
index f8c5b8babb..ddb1a7c09d 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutorFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SequencedSkyframeExecutorFactory.java
@@ -19,6 +19,7 @@ import com.google.devtools.build.lib.actions.ActionKeyContext;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.WorkspaceStatusAction.Factory;
 import com.google.devtools.build.lib.analysis.buildinfo.BuildInfoFactory;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.packages.PackageFactory;
 import com.google.devtools.build.lib.vfs.FileSystem;
 import com.google.devtools.build.skyframe.SkyFunction;
@@ -29,6 +30,12 @@ import com.google.devtools.build.skyframe.SkyFunctionName;
  */
 public class SequencedSkyframeExecutorFactory implements SkyframeExecutorFactory {
 
+  private final BuildOptions defaultBuildOptions;
+
+  public SequencedSkyframeExecutorFactory(BuildOptions defaultBuildOptions) {
+    this.defaultBuildOptions = defaultBuildOptions;
+  }
+
   @Override
   public SkyframeExecutor create(
       PackageFactory pkgFactory,
@@ -54,6 +61,7 @@ public class SequencedSkyframeExecutorFactory implements SkyframeExecutorFactory
         BazelSkyframeExecutorConstants.ADDITIONAL_BLACKLISTED_PACKAGE_PREFIXES_FILE,
         BazelSkyframeExecutorConstants.CROSS_REPOSITORY_LABEL_VIOLATION_STRATEGY,
         BazelSkyframeExecutorConstants.BUILD_FILES_BY_PRIORITY,
-        BazelSkyframeExecutorConstants.ACTION_ON_IO_EXCEPTION_READING_BUILD_FILE);
+        BazelSkyframeExecutorConstants.ACTION_ON_IO_EXCEPTION_READING_BUILD_FILE,
+        defaultBuildOptions);
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeBuildView.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeBuildView.java
index 3cb34515df..115c5c1fa8 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeBuildView.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeBuildView.java
@@ -126,7 +126,8 @@ public final class SkyframeBuildView {
 
   public SkyframeBuildView(BlazeDirectories directories,
       SkyframeExecutor skyframeExecutor, ConfiguredRuleClassProvider ruleClassProvider) {
-    this.factory = new ConfiguredTargetFactory(ruleClassProvider);
+    this.factory =
+        new ConfiguredTargetFactory(ruleClassProvider, skyframeExecutor.getDefaultBuildOptions());
     this.artifactFactory =
         new ArtifactFactory(directories.getExecRoot(), directories.getRelativeOutputPath());
     this.skyframeExecutor = skyframeExecutor;
@@ -568,7 +569,8 @@ public final class SkyframeBuildView {
     // case. So further optimization is necessary to make that viable (proto_library in particular
     // contributes to much of the difference).
     BuildConfiguration trimmedConfig =
-        topLevelHostConfiguration.clone(fragmentClasses, ruleClassProvider);
+        topLevelHostConfiguration.clone(
+            fragmentClasses, ruleClassProvider, skyframeExecutor.getDefaultBuildOptions());
     hostConfigurationCache.put(fragmentClasses, trimmedConfig);
     return trimmedConfig;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeDependencyResolver.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeDependencyResolver.java
index 8b3d23daf5..f4940066c8 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeDependencyResolver.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeDependencyResolver.java
@@ -124,11 +124,15 @@ public final class SkyframeDependencyResolver extends DependencyResolver {
   @Nullable
   @Override
   protected List<BuildConfiguration> getConfigurations(
-      FragmentClassSet fragments, Iterable<BuildOptions> buildOptions)
+      FragmentClassSet fragments,
+      Iterable<BuildOptions> buildOptions,
+      BuildOptions defaultBuildOptions)
       throws InvalidConfigurationException, InterruptedException {
     List<SkyKey> keys = new ArrayList<>();
     for (BuildOptions options : buildOptions) {
-      keys.add(BuildConfigurationValue.key(fragments, options));
+      keys.add(
+          BuildConfigurationValue.key(
+              fragments, BuildOptions.diffForReconstruction(defaultBuildOptions, options)));
     }
     Map<SkyKey, ValueOrException<InvalidConfigurationException>> configValues =
         env.getValuesOrThrow(keys, InvalidConfigurationException.class);
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
index d5c54471a3..d8686adf31 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
@@ -293,6 +293,8 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
 
   private final ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile;
 
+  private final BuildOptions defaultBuildOptions;
+
   private PerBuildSyscallCache perBuildSyscallCache;
   private int lastConcurrencyLevel = -1;
 
@@ -312,7 +314,8 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
       PathFragment additionalBlacklistedPackagePrefixesFile,
       CrossRepositoryLabelViolationStrategy crossRepositoryLabelViolationStrategy,
       List<BuildFileName> buildFilesByPriority,
-      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile) {
+      ActionOnIOExceptionReadingBuildFile actionOnIOExceptionReadingBuildFile,
+      BuildOptions defaultBuildOptions) {
     // Strictly speaking, these arguments are not required for initialization, but all current
     // callsites have them at hand, so we might as well set them during construction.
     this.evaluatorSupplier = evaluatorSupplier;
@@ -338,6 +341,7 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
     this.additionalBlacklistedPackagePrefixesFile = additionalBlacklistedPackagePrefixesFile;
 
     this.ruleClassProvider = pkgFactory.getRuleClassProvider();
+    this.defaultBuildOptions = defaultBuildOptions;
     this.skyframeBuildView = new SkyframeBuildView(
         directories,
         this,
@@ -423,19 +427,24 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
             ruleClassProvider,
             cpuBoundSemaphore,
             removeActionsAfterEvaluation,
-            shouldStoreTransitivePackagesInLoadingAndAnalysis()));
+            shouldStoreTransitivePackagesInLoadingAndAnalysis(),
+            defaultBuildOptions));
     map.put(
         SkyFunctions.ASPECT,
         new AspectFunction(
             new BuildViewProvider(),
             ruleClassProvider,
             removeActionsAfterEvaluation,
-            shouldStoreTransitivePackagesInLoadingAndAnalysis()));
+            shouldStoreTransitivePackagesInLoadingAndAnalysis(),
+            defaultBuildOptions));
     map.put(SkyFunctions.LOAD_SKYLARK_ASPECT, new ToplevelSkylarkAspectFunction());
-    map.put(SkyFunctions.POST_CONFIGURED_TARGET,
-        new PostConfiguredTargetFunction(new BuildViewProvider(), ruleClassProvider));
-    map.put(SkyFunctions.BUILD_CONFIGURATION,
-        new BuildConfigurationFunction(directories, ruleClassProvider));
+    map.put(
+        SkyFunctions.POST_CONFIGURED_TARGET,
+        new PostConfiguredTargetFunction(
+            new BuildViewProvider(), ruleClassProvider, defaultBuildOptions));
+    map.put(
+        SkyFunctions.BUILD_CONFIGURATION,
+        new BuildConfigurationFunction(directories, ruleClassProvider, defaultBuildOptions));
     map.put(
         SkyFunctions.CONFIGURATION_FRAGMENT,
         new ConfigurationFragmentFunction(configurationFragments, ruleClassProvider, directories));
@@ -907,7 +916,9 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
         requiredToolchains,
         config == null
             ? null
-            : BuildConfigurationValue.key(config.fragmentClasses(), config.getOptions()));
+            : BuildConfigurationValue.key(
+                config.fragmentClasses(),
+                BuildOptions.diffForReconstruction(defaultBuildOptions, config.getOptions())));
   }
 
   /**
@@ -1299,6 +1310,11 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
     return getConfiguredTargetMapForTesting(eventHandler, originalConfig, keys).values().asList();
   }
 
+  @VisibleForTesting
+  public BuildOptions getDefaultBuildOptions() {
+    return defaultBuildOptions;
+  }
+
   /**
    * Returns a map from {@link Dependency} inputs to the {@link ConfiguredTargetAndData}s
    * corresponding to those dependencies.
@@ -1457,7 +1473,11 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
     final ImmutableList<SkyKey> configSkyKeys =
         optionsList
             .stream()
-            .map(elem -> BuildConfigurationValue.key(allFragments, elem))
+            .map(
+                elem ->
+                    BuildConfigurationValue.key(
+                        allFragments,
+                        BuildOptions.diffForReconstruction(defaultBuildOptions, elem)))
             .collect(ImmutableList.toImmutableList());
 
     // Skyframe-evaluate the configurations and throw errors if any.
@@ -1554,7 +1574,10 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
       if (depFragments != null) {
         for (BuildOptions toOptions : ConfigurationResolver.applyTransition(
             fromOptions, key.getTransition(), depFragments, ruleClassProvider, true)) {
-          configSkyKeys.add(BuildConfigurationValue.key(depFragments, toOptions));
+          configSkyKeys.add(
+              BuildConfigurationValue.key(
+                  depFragments,
+                  BuildOptions.diffForReconstruction(defaultBuildOptions, toOptions)));
         }
       }
     }
@@ -1569,7 +1592,9 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
       if (depFragments != null) {
         for (BuildOptions toOptions : ConfigurationResolver.applyTransition(
             fromOptions, key.getTransition(), depFragments, ruleClassProvider, true)) {
-          SkyKey configKey = BuildConfigurationValue.key(depFragments, toOptions);
+          SkyKey configKey =
+              BuildConfigurationValue.key(
+                  depFragments, BuildOptions.diffForReconstruction(defaultBuildOptions, toOptions));
           BuildConfigurationValue configValue =
               ((BuildConfigurationValue) configsResult.get(configKey));
           // configValue will be null here if there was an exception thrown during configuration
@@ -1640,7 +1665,9 @@ public abstract class SkyframeExecutor implements WalkableGraphFactory {
       FragmentClassSet fragments,
       BuildOptions options)
       throws InterruptedException {
-    SkyKey key = BuildConfigurationValue.key(fragments, options);
+    SkyKey key =
+        BuildConfigurationValue.key(
+            fragments, BuildOptions.diffForReconstruction(defaultBuildOptions, options));
     BuildConfigurationValue result = (BuildConfigurationValue) buildDriver
         .evaluate(ImmutableList.of(key), false, DEFAULT_THREAD_COUNT, eventHandler).get(key);
     return result.getConfiguration();