Implement the fully link action in the OSX crosstool.

--
MOS_MIGRATED_REVID=130547971

9 files changed, 270 insertions, 160 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkActionBuilder.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkActionBuilder.java
index 15bde7883e..4fcc90c23d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkActionBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkActionBuilder.java
@@ -822,11 +822,17 @@ public class CppLinkActionBuilder {
     return this;
   }
 
-  /**
-   * Adds variables extensions to template the toolchain for this link action.
-   */
-   public CppLinkActionBuilder addVariablesExtension(List<VariablesExtension> variablesExtensions) {
-     this.variablesExtensions.addAll(variablesExtensions);
+  /** Adds a variables extension to template the toolchain for this link action. */
+  public CppLinkActionBuilder addVariablesExtension(VariablesExtension variablesExtension) {
+    this.variablesExtensions.add(variablesExtension);
+    return this;
+  }
+
+  /** Adds variables extensions to template the toolchain for this link action. */
+  public CppLinkActionBuilder addVariablesExtensions(List<VariablesExtension> variablesExtensions) {
+    for (VariablesExtension variablesExtension : variablesExtensions) {
+      addVariablesExtension(variablesExtension);
+    }
      return this;
    }
   
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModel.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModel.java
index 8e0120efe0..a1c9644ef7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModel.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModel.java
@@ -872,7 +872,7 @@ public final class CppModel {
             .setLinkStaticness(LinkStaticness.FULLY_STATIC)
             .addActionInputs(linkActionInputs)
             .setLibraryIdentifier(libraryIdentifier)
-            .addVariablesExtension(variablesExtensions)
+            .addVariablesExtensions(variablesExtensions)
             .setFeatureConfiguration(featureConfiguration)
             .build();
     env.registerAction(maybePicAction);
@@ -901,7 +901,7 @@ public final class CppModel {
               .setLinkStaticness(LinkStaticness.FULLY_STATIC)
               .addActionInputs(linkActionInputs)
               .setLibraryIdentifier(libraryIdentifier)
-              .addVariablesExtension(variablesExtensions)
+              .addVariablesExtensions(variablesExtensions)
               .setFeatureConfiguration(featureConfiguration)
               .build();
       env.registerAction(picAction);
@@ -961,7 +961,7 @@ public final class CppModel {
                 CppHelper.getToolchain(ruleContext).getDynamicRuntimeLinkMiddleman(),
                 CppHelper.getToolchain(ruleContext).getDynamicRuntimeLinkInputs())
             .setFeatureConfiguration(featureConfiguration)
-            .addVariablesExtension(variablesExtensions);
+            .addVariablesExtensions(variablesExtensions);
 
     if (!ccOutputs.getLtoBitcodeFiles().isEmpty()
         && featureConfiguration.isEnabled(CppRuleClasses.THIN_LTO)) {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/Link.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/Link.java
index a6288e5eed..f03f128199 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/Link.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/Link.java
@@ -128,6 +128,10 @@ public abstract class Link {
         "objc-archive", 
         Picness.NOPIC,
         ArtifactCategory.STATIC_LIBRARY),
+    
+    /** An objc fully linked static archive. */
+    OBJC_FULLY_LINKED_ARCHIVE(
+        ".a", Staticness.STATIC, "objc-fully-link", Picness.NOPIC, ArtifactCategory.STATIC_LIBRARY),
 
     /** A static archive with .pic.o object files (compiled with -fPIC). */
     PIC_STATIC_LIBRARY(
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java
index a3a01aefb0..b3a0cc7d09 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/LinkCommandLine.java
@@ -443,6 +443,7 @@ public final class LinkCommandLine extends CommandLine {
         // Since the objc case is not hardcoded in CppConfiguration, we can use the actual tool.
         // TODO(b/30109612): make this pattern the case for all link variants.
       case OBJC_ARCHIVE:
+      case OBJC_FULLY_LINKED_ARCHIVE:
         argv.add(
             featureConfiguration
                 .getToolForAction(actionName)
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
index 102b018802..4da2ff3eab 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationSupport.java
@@ -85,7 +85,6 @@ import com.google.devtools.build.lib.rules.apple.Platform;
 import com.google.devtools.build.lib.rules.apple.Platform.PlatformType;
 import com.google.devtools.build.lib.rules.cpp.CppModuleMap;
 import com.google.devtools.build.lib.rules.cpp.CppModuleMapAction;
-import com.google.devtools.build.lib.rules.cpp.LinkerInputs;
 import com.google.devtools.build.lib.rules.objc.XcodeProvider.Builder;
 import com.google.devtools.build.lib.rules.test.InstrumentedFilesCollector;
 import com.google.devtools.build.lib.rules.test.InstrumentedFilesCollector.InstrumentationSpec;
@@ -1019,8 +1018,8 @@ public final class CompilationSupport {
       throws InterruptedException {
     Artifact outputArchive =
         ruleContext.getImplicitOutputArtifact(CompilationSupport.FULLY_LINKED_LIB);
-    ImmutableList<Artifact> objcLibraries = objcLibraries(objcProvider);
-    ImmutableList<Artifact> ccLibraries = ccLibraries(objcProvider);
+    ImmutableList<Artifact> objcLibraries = objcProvider.getObjcLibraries();
+    ImmutableList<Artifact> ccLibraries = objcProvider.getCcLibraries();
     ruleContext.registerAction(ObjcRuleClasses.spawnAppleEnvActionBuilder(
             appleConfiguration, appleConfiguration.getSingleArchPlatform())
         .setMnemonic("ObjcLink")
@@ -1214,8 +1213,8 @@ public final class CompilationSupport {
             ? intermediateArtifacts.unstrippedSingleArchitectureBinary()
             : intermediateArtifacts.strippedSingleArchitectureBinary();
 
-    ImmutableList<Artifact> objcLibraries = objcLibraries(objcProvider);
-    ImmutableList<Artifact> ccLibraries = ccLibraries(objcProvider);
+    ImmutableList<Artifact> objcLibraries = objcProvider.getObjcLibraries();
+    ImmutableList<Artifact> ccLibraries = objcProvider.getCcLibraries();
     ImmutableList<Artifact> bazelBuiltLibraries = Iterables.isEmpty(prunedJ2ObjcArchives)
         ? objcLibraries : substituteJ2ObjcPrunedLibraries(objcProvider);
     CommandLine commandLine =
@@ -1274,24 +1273,6 @@ public final class CompilationSupport {
     }
   }
 
-  private ImmutableList<Artifact> objcLibraries(ObjcProvider objcProvider) {
-    ImmutableList.Builder<Artifact> objcLibraryBuilder = ImmutableList.builder();
-    // JRE libraries must be ordered after all regular objc libraries.
-    NestedSet<Artifact> jreLibs = objcProvider.get(ObjcProvider.JRE_LIBRARY);
-    objcLibraryBuilder.addAll(Iterables.filter(
-        objcProvider.get(LIBRARY), Predicates.not(Predicates.in(jreLibs.toSet()))));
-    objcLibraryBuilder.addAll(jreLibs);
-    return objcLibraryBuilder.build();
-  }
-
-  private ImmutableList<Artifact> ccLibraries(ObjcProvider objcProvider) {
-    ImmutableList.Builder<Artifact> ccLibraryBuilder = ImmutableList.builder();
-    for (LinkerInputs.LibraryToLink libraryToLink : objcProvider.get(ObjcProvider.CC_LIBRARY)) {
-      ccLibraryBuilder.add(libraryToLink.getArtifact());
-    }
-    return ccLibraryBuilder.build();
-  }
-
   private ImmutableList<Artifact> j2objcPrunedLibraries(ObjcProvider objcProvider) {
     ImmutableList.Builder<Artifact> j2objcPrunedLibraryBuilder = ImmutableList.builder();
     for (Artifact j2objcLibrary : objcProvider.get(ObjcProvider.J2OBJC_LIBRARY)) {
@@ -1318,7 +1299,7 @@ public final class CompilationSupport {
     ImmutableList.Builder<Artifact> libraries = new ImmutableList.Builder<>();
 
     Set<Artifact> unprunedJ2ObjcLibs = objcProvider.get(ObjcProvider.J2OBJC_LIBRARY).toSet();
-    for (Artifact library : objcLibraries(objcProvider)) {
+    for (Artifact library : objcProvider.getObjcLibraries()) {
       // If we match an unpruned J2ObjC library, add the pruned version of the J2ObjC static library
       // instead.
       if (unprunedJ2ObjcLibs.contains(library)) {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java
index f02a63e988..5de560630b 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibrary.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.rules.objc;
 
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.DEFINE;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.IMPORTED_LIBRARY;
 import static com.google.devtools.build.lib.rules.objc.XcodeProductType.LIBRARY_STATIC;
 
 import com.google.common.collect.ImmutableList;
@@ -27,125 +28,26 @@ import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
-import com.google.devtools.build.lib.rules.apple.Platform;
 import com.google.devtools.build.lib.rules.cpp.CcLibraryHelper;
-import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.FeatureConfiguration;
-import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.Variables.ValueSequence;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.Variables.VariablesExtension;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainProvider;
+import com.google.devtools.build.lib.rules.cpp.CppLinkAction;
+import com.google.devtools.build.lib.rules.cpp.CppLinkActionBuilder;
 import com.google.devtools.build.lib.rules.cpp.CppRuleClasses;
+import com.google.devtools.build.lib.rules.cpp.Link.LinkStaticness;
 import com.google.devtools.build.lib.rules.cpp.Link.LinkTargetType;
 import com.google.devtools.build.lib.rules.cpp.PrecompiledFiles;
 import com.google.devtools.build.lib.rules.objc.ObjcCommon.ResourceAttributes;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
 
 /** Implementation for experimental_objc_library. */
 public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
 
-  private static final String PCH_FILE_VARIABLE_NAME = "pch_file";
-  private static final String FRAMEWORKS_VARIABLE_NAME = "framework_paths";
-  private static final String VERSION_MIN_VARIABLE_NAME = "version_min";
-  private static final String MODULES_MAPS_DIR_NAME = "module_maps_dir";
-  private static final String OBJC_MODULE_CACHE_DIR_NAME = "_objc_module_cache";
-  private static final String OBJC_MODULE_CACHE_KEY = "modules_cache_path";
   private static final String OBJC_MODULE_FEATURE_NAME = "use_objc_modules";
-  private static final String OBJ_LIST_PATH_VARIABLE_NAME = "obj_list_path";
-  private static final String ARCHIVE_PATH_VARIABLE_NAME = "archive_path";
   private static final Iterable<String> ACTIVATED_ACTIONS =
-      ImmutableList.of("objc-compile", "objc++-compile", "objc-archive");
-
-  /** Build variable extensions for templating a toolchain for objc builds. */
-  static class ObjcVariablesExtension implements VariablesExtension {
-
-    private final RuleContext ruleContext;
-    private final ObjcProvider objcProvider;
-    private final CompilationArtifacts compilationArtifacts;
-
-    private final AppleConfiguration appleConfiguration;
-    private final ObjcConfiguration objcConfiguration;
-
-    public ObjcVariablesExtension(
-        RuleContext ruleContext,
-        ObjcProvider objcProvider,
-        CompilationArtifacts compilationArtifacts) {
-      this.ruleContext = ruleContext;
-      this.objcProvider = objcProvider;
-      this.compilationArtifacts = compilationArtifacts;
-
-      this.appleConfiguration = ruleContext.getFragment(AppleConfiguration.class);
-      this.objcConfiguration = ruleContext.getFragment(ObjcConfiguration.class);
-    }
-  
-    @Override
-    public void addVariables(CcToolchainFeatures.Variables.Builder builder) {
-      addPchVariables(builder);
-      addFrameworkVariables(builder);
-      addArchVariables(builder);
-      if (ObjcCommon.shouldUseObjcModules(ruleContext)) {
-        addModuleMapVariables(builder);
-      }
-      if (isStaticArchive(compilationArtifacts)) {
-        addArchiveVariables(builder);
-      }
-    }
-
-    private void addPchVariables(CcToolchainFeatures.Variables.Builder builder) {
-      if (ruleContext.getPrerequisiteArtifact("pch", Mode.TARGET) != null) {
-        builder.addVariable(
-            PCH_FILE_VARIABLE_NAME,
-            ruleContext.getPrerequisiteArtifact("pch", Mode.TARGET).getExecPathString());
-      }
-    }
-  
-    private void addFrameworkVariables(CcToolchainFeatures.Variables.Builder builder) {
-      ValueSequence.Builder frameworkSequence = new ValueSequence.Builder();
-      AppleConfiguration appleConfig = ruleContext.getFragment(AppleConfiguration.class);
-      for (String framework : CompilationSupport.commonFrameworkNames(objcProvider, appleConfig)) {
-        frameworkSequence.addValue(framework);
-      }
-      builder.addSequence(FRAMEWORKS_VARIABLE_NAME, frameworkSequence.build());
-    }
-  
-    private void addModuleMapVariables(CcToolchainFeatures.Variables.Builder builder) {
-      builder.addVariable(
-          MODULES_MAPS_DIR_NAME,
-          ObjcRuleClasses.intermediateArtifacts(ruleContext)
-              .moduleMap()
-              .getArtifact()
-              .getExecPath()
-              .getParentDirectory()
-              .toString());
-      builder.addVariable(
-          OBJC_MODULE_CACHE_KEY,
-          ruleContext.getConfiguration().getGenfilesFragment() + "/" + OBJC_MODULE_CACHE_DIR_NAME);
-    }
-    
-    private void addArchVariables(CcToolchainFeatures.Variables.Builder builder) {
-      Platform platform = appleConfiguration.getSingleArchPlatform();
-      switch (platform.getType()) {
-        case IOS:
-          builder.addVariable(
-              VERSION_MIN_VARIABLE_NAME, objcConfiguration.getMinimumOs().toString());
-          break;
-        case WATCHOS:
-          builder.addVariable(
-              VERSION_MIN_VARIABLE_NAME,
-              appleConfiguration.getSdkVersionForPlatform(platform).toString());
-          break;
-        default: // don't handle MACOS and TVOS
-          throw new IllegalArgumentException("Unhandled platform: " + platform);
-      }
-    }
-    
-    private void addArchiveVariables(CcToolchainFeatures.Variables.Builder builder) {
-      builder.addVariable(
-          OBJ_LIST_PATH_VARIABLE_NAME,
-          ObjcRuleClasses.intermediateArtifacts(ruleContext).archiveObjList().getExecPathString());
-      builder.addVariable(
-          ARCHIVE_PATH_VARIABLE_NAME, compilationArtifacts.getArchive().get().getExecPathString());
-    }
-  }
+      ImmutableList.of("objc-compile", "objc++-compile", "objc-archive", "objc-fully-link");
 
   @Override
   public ConfiguredTarget create(RuleContext ruleContext)
@@ -162,6 +64,16 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
         ObjcRuleClasses.intermediateArtifacts(ruleContext);
 
     ObjcCommon common = common(ruleContext, compilationAttributes, compilationArtifacts);
+    ObjcVariablesExtension variablesExtension =
+        new ObjcVariablesExtension(
+            ruleContext,
+            common.getObjcProvider(),
+            compilationArtifacts,
+            ruleContext.getImplicitOutputArtifact(CompilationSupport.FULLY_LINKED_LIB),
+            intermediateArtifacts,
+            ruleContext.getConfiguration());
+
+    FeatureConfiguration featureConfiguration = getFeatureConfiguration(ruleContext);
 
     Collection<Artifact> arcSources = Sets.newHashSet(compilationArtifacts.getSrcs());
     Collection<Artifact> nonArcSources = Sets.newHashSet(compilationArtifacts.getNonArcSrcs());
@@ -172,7 +84,7 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
         new CcLibraryHelper(
                 ruleContext,
                 new ObjcCppSemantics(common.getObjcProvider()),
-                getFeatureConfiguration(ruleContext),
+                featureConfiguration,
                 CcLibraryHelper.SourceCategory.CC_AND_OBJC)
             .addSources(arcSources, ImmutableMap.of("objc_arc", ""))
             .addSources(nonArcSources, ImmutableMap.of("no_objc_arc", ""))
@@ -183,21 +95,13 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
             .addPrecompiledFiles(precompiledFiles)
             .addDeps(ruleContext.getPrerequisites("deps", Mode.TARGET))
             .addCopts(compilationSupport.getCompileRuleCopts())
-            .addVariableExtension(
-                new ObjcVariablesExtension(
-                    ruleContext, common.getObjcProvider(), compilationArtifacts));
-
-    if (isStaticArchive(compilationArtifacts)) {
-      Artifact objList = intermediateArtifacts.archiveObjList();
+            .addVariableExtension(variablesExtension);
 
-      // TODO(b/30783125): Signal the need for this action in the CROSSTOOL.
-      compilationSupport.registerObjFilelistAction(
-          getObjFiles(compilationArtifacts, intermediateArtifacts), objList);
-
-      helper
-          .setLinkType(LinkTargetType.OBJC_ARCHIVE)
-          .addLinkActionInput(objList);
+    if (compilationArtifacts.getArchive().isPresent()) {
+      registerArchiveAction(
+          intermediateArtifacts, compilationSupport, compilationArtifacts, helper);
     }
+    registerFullyLinkAction(ruleContext, common, variablesExtension, featureConfiguration);
 
     if (ObjcCommon.shouldUseObjcModules(ruleContext)) {
       helper.setCppModuleMap(ObjcRuleClasses.intermediateArtifacts(ruleContext).moduleMap());
@@ -222,6 +126,7 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
     return ObjcRuleClasses.ruleConfiguredTarget(ruleContext, filesToBuild.build())
         .addProvider(ObjcProvider.class, common.getObjcProvider())
         .addProviders(info.getProviders())
+        .addProvider(ObjcProvider.class, common.getObjcProvider())
         .addProvider(XcodeProvider.class, xcodeProviderBuilder.build())
         .build();
   }
@@ -254,9 +159,49 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
     return toolchain.getFeatures().getFeatureConfiguration(activatedCrosstoolSelectables.build());
   }
 
-  /**
-   * Throws errors or warnings for bad attribute state.
-   */
+  private void registerArchiveAction(
+      IntermediateArtifacts intermediateArtifacts,
+      CompilationSupport compilationSupport,
+      CompilationArtifacts compilationArtifacts,
+      CcLibraryHelper helper) {
+    Artifact objList = intermediateArtifacts.archiveObjList();
+
+    // TODO(b/30783125): Signal the need for this action in the CROSSTOOL.
+    compilationSupport.registerObjFilelistAction(
+        getObjFiles(compilationArtifacts, intermediateArtifacts), objList);
+
+    helper.setLinkType(LinkTargetType.OBJC_ARCHIVE).addLinkActionInput(objList);
+  }
+
+  private void registerFullyLinkAction(
+      RuleContext ruleContext,
+      ObjcCommon common,
+      VariablesExtension variablesExtension,
+      FeatureConfiguration featureConfiguration)
+      throws InterruptedException {
+    Artifact fullyLinkedArchive =
+        ruleContext.getImplicitOutputArtifact(CompilationSupport.FULLY_LINKED_LIB);
+    PathFragment labelName = new PathFragment(ruleContext.getLabel().getName());
+    String libraryIdentifier =
+        ruleContext
+            .getPackageDirectory()
+            .getRelative(labelName.replaceName("lib" + labelName.getBaseName()))
+            .getPathString();
+    CppLinkAction fullyLinkAction =
+        new CppLinkActionBuilder(ruleContext, fullyLinkedArchive)
+            .addActionInputs(common.getObjcProvider().getObjcLibraries())
+            .addActionInputs(common.getObjcProvider().getCcLibraries())
+            .addActionInputs(common.getObjcProvider().get(IMPORTED_LIBRARY).toSet())
+            .setLinkType(LinkTargetType.OBJC_FULLY_LINKED_ARCHIVE)
+            .setLinkStaticness(LinkStaticness.FULLY_STATIC)
+            .setLibraryIdentifier(libraryIdentifier)
+            .addVariablesExtension(variablesExtension)
+            .setFeatureConfiguration(featureConfiguration)
+            .build();
+    ruleContext.registerAction(fullyLinkAction);
+  }
+
+  /** Throws errors or warnings for bad attribute state. */
   private void validateAttributes(RuleContext ruleContext) {
     for (String copt : ObjcCommon.getNonCrosstoolCopts(ruleContext)) {
       if (copt.contains("-fmodules-cache-path")) {
@@ -282,11 +227,7 @@ public class ExperimentalObjcLibrary implements RuleConfiguredTargetFactory {
         .setIntermediateArtifacts(ObjcRuleClasses.intermediateArtifacts(ruleContext))
         .build();
   }
-  
-  private static boolean isStaticArchive(CompilationArtifacts compilationArtifacts) {
-    return compilationArtifacts.getArchive().isPresent();
-  }
-
+ 
   private ImmutableList<Artifact> getObjFiles(
       CompilationArtifacts compilationArtifacts, IntermediateArtifacts intermediateArtifacts) {
     ImmutableList.Builder<Artifact> result = new ImmutableList.Builder<>();
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibraryRule.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibraryRule.java
index 42959fc43e..85014c37e8 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibraryRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ExperimentalObjcLibraryRule.java
@@ -32,7 +32,9 @@ public class ExperimentalObjcLibraryRule implements RuleDefinition {
     return builder
         .requiresConfigurationFragments(
             ObjcConfiguration.class, AppleConfiguration.class, CppConfiguration.class)
-        .setImplicitOutputsFunction(ImplicitOutputsFunction.fromFunctions(XcodeSupport.PBXPROJ))
+        .setImplicitOutputsFunction(
+            ImplicitOutputsFunction.fromFunctions(
+                CompilationSupport.FULLY_LINKED_LIB, XcodeSupport.PBXPROJ))
         .build();
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
index 4051f81ff5..40ed2b1c73 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
@@ -17,6 +17,7 @@ package com.google.devtools.build.lib.rules.objc;
 import static com.google.devtools.build.lib.collect.nestedset.Order.LINK_ORDER;
 import static com.google.devtools.build.lib.collect.nestedset.Order.STABLE_ORDER;
 
+import com.google.common.base.Predicates;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
@@ -32,7 +33,6 @@ import com.google.devtools.build.lib.rules.cpp.CppModuleMap;
 import com.google.devtools.build.lib.rules.cpp.LinkerInputs;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
-import com.google.devtools.build.lib.syntax.Concatable.Concatter;
 import com.google.devtools.build.lib.syntax.EvalUtils;
 import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -470,6 +470,26 @@ public final class ObjcProvider extends SkylarkClassObject implements Transitive
     return !get(XCASSETS_DIR).isEmpty();
   }
 
+  /** Returns the list of .a files required for linking that arise from objc libraries. */
+  ImmutableList<Artifact> getObjcLibraries() {
+    // JRE libraries must be ordered after all regular objc libraries.
+    NestedSet<Artifact> jreLibs = get(JRE_LIBRARY);
+    return ImmutableList.<Artifact>builder()
+        .addAll(Iterables.filter(
+            get(LIBRARY), Predicates.not(Predicates.in(jreLibs.toSet()))))
+        .addAll(jreLibs)
+        .build();
+  }
+
+  /** Returns the list of .a files required for linking that arise from cc libraries. */
+  ImmutableList<Artifact> getCcLibraries() {
+    ImmutableList.Builder<Artifact> ccLibraryBuilder = ImmutableList.builder();
+    for (LinkerInputs.LibraryToLink libraryToLink : get(CC_LIBRARY)) {
+      ccLibraryBuilder.add(libraryToLink.getArtifact());
+    }
+    return ccLibraryBuilder.build();
+  }
+
   /**
    * A builder for this context with an API that is optimized for collecting information from
    * several transitive dependencies.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcVariablesExtension.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcVariablesExtension.java
new file mode 100644
index 0000000000..70fc868af9
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcVariablesExtension.java
@@ -0,0 +1,155 @@
+// Copyright 2016 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.rules.objc;
+
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.IMPORTED_LIBRARY;
+
+import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
+import com.google.devtools.build.lib.rules.apple.Platform;
+import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures;
+import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.Variables.ValueSequence;
+import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.Variables.VariablesExtension;
+
+/** Build variable extensions for templating a toolchain for objc builds. */
+class ObjcVariablesExtension implements VariablesExtension {
+
+  static final String PCH_FILE_VARIABLE_NAME = "pch_file";
+  static final String FRAMEWORKS_VARIABLE_NAME = "framework_paths";
+  static final String VERSION_MIN_VARIABLE_NAME = "version_min";
+  static final String MODULES_MAPS_DIR_NAME = "module_maps_dir";
+  static final String OBJC_MODULE_CACHE_DIR_NAME = "_objc_module_cache";
+  static final String OBJC_MODULE_CACHE_KEY = "modules_cache_path";
+  static final String OBJ_LIST_PATH_VARIABLE_NAME = "obj_list_path";
+  static final String ARCHIVE_PATH_VARIABLE_NAME = "archive_path";
+  static final String FULLY_LINKED_ARCHIVE_PATH_VARIABLE_NAME = "fully_linked_archive_path";
+  static final String OBJC_LIBRARY_EXEC_PATHS_VARIABLE_NAME = "objc_library_exec_paths";
+  static final String CC_LIBRARY_EXEC_PATHS_VARIABLE_NAME = "cc_library_exec_paths";
+  static final String IMPORTED_LIBRARY_EXEC_PATHS_VARIABLE_NAME = "imported_library_exec_paths";
+
+  private final RuleContext ruleContext;
+  private final ObjcProvider objcProvider;
+  private final CompilationArtifacts compilationArtifacts;
+  private final Artifact fullyLinkArchive;
+  private final IntermediateArtifacts intermediateArtifacts;
+
+  private final BuildConfiguration buildConfiguration;
+  private final AppleConfiguration appleConfiguration;
+  private final ObjcConfiguration objcConfiguration;
+
+  public ObjcVariablesExtension(
+      RuleContext ruleContext,
+      ObjcProvider objcProvider,
+      CompilationArtifacts compilationArtifacts,
+      Artifact fullyLinkArchive,
+      IntermediateArtifacts intermediateArtifacts,
+      BuildConfiguration buildConfiguration) {
+    this.ruleContext = ruleContext;
+    this.objcProvider = objcProvider;
+    this.compilationArtifacts = compilationArtifacts;
+    this.fullyLinkArchive = fullyLinkArchive;
+    this.intermediateArtifacts = intermediateArtifacts;
+    this.buildConfiguration = buildConfiguration;
+    this.objcConfiguration = buildConfiguration.getFragment(ObjcConfiguration.class);
+    this.appleConfiguration = buildConfiguration.getFragment(AppleConfiguration.class);
+  }
+
+  @Override
+  public void addVariables(CcToolchainFeatures.Variables.Builder builder) {
+    addPchVariables(builder);
+    addFrameworkVariables(builder);
+    addArchVariables(builder);
+    if (ObjcCommon.shouldUseObjcModules(ruleContext)) {
+      addModuleMapVariables(builder);
+    }
+    if (compilationArtifacts.getArchive().isPresent()) {
+      addArchiveVariables(builder);
+    }
+    addFullyLinkArchiveVariables(builder);
+  }
+
+  private void addPchVariables(CcToolchainFeatures.Variables.Builder builder) {
+    if (ruleContext.getPrerequisiteArtifact("pch", Mode.TARGET) != null) {
+      builder.addVariable(
+          PCH_FILE_VARIABLE_NAME,
+          ruleContext.getPrerequisiteArtifact("pch", Mode.TARGET).getExecPathString());
+    }
+  }
+
+  private void addFrameworkVariables(CcToolchainFeatures.Variables.Builder builder) {
+    ValueSequence.Builder frameworkSequence = new ValueSequence.Builder();
+    for (String framework :
+        CompilationSupport.commonFrameworkNames(objcProvider, appleConfiguration)) {
+      frameworkSequence.addValue(framework);
+    }
+    builder.addSequence(FRAMEWORKS_VARIABLE_NAME, frameworkSequence.build());
+  }
+
+  private void addModuleMapVariables(CcToolchainFeatures.Variables.Builder builder) {
+    builder.addVariable(
+        MODULES_MAPS_DIR_NAME,
+        intermediateArtifacts
+            .moduleMap()
+            .getArtifact()
+            .getExecPath()
+            .getParentDirectory()
+            .toString());
+    builder.addVariable(
+        OBJC_MODULE_CACHE_KEY,
+        buildConfiguration.getGenfilesFragment() + "/" + OBJC_MODULE_CACHE_DIR_NAME);
+  }
+
+  private void addArchVariables(CcToolchainFeatures.Variables.Builder builder) {
+    Platform platform = appleConfiguration.getSingleArchPlatform();
+    switch (platform.getType()) {
+      case IOS:
+        builder.addVariable(VERSION_MIN_VARIABLE_NAME, objcConfiguration.getMinimumOs().toString());
+        break;
+      case WATCHOS:
+        builder.addVariable(
+            VERSION_MIN_VARIABLE_NAME,
+            appleConfiguration.getSdkVersionForPlatform(platform).toString());
+        break;
+      default:
+        throw new IllegalArgumentException("Unhandled platform: " + platform);
+    }
+  }
+
+  private void addArchiveVariables(CcToolchainFeatures.Variables.Builder builder) {
+    builder.addVariable(
+        OBJ_LIST_PATH_VARIABLE_NAME,
+        ObjcRuleClasses.intermediateArtifacts(ruleContext).archiveObjList().getExecPathString());
+    builder.addVariable(
+        ARCHIVE_PATH_VARIABLE_NAME, compilationArtifacts.getArchive().get().getExecPathString());
+  }
+
+  private void addFullyLinkArchiveVariables(CcToolchainFeatures.Variables.Builder builder) {
+    builder.addVariable(
+        FULLY_LINKED_ARCHIVE_PATH_VARIABLE_NAME, fullyLinkArchive.getExecPathString());
+    builder.addSequenceVariable(
+        OBJC_LIBRARY_EXEC_PATHS_VARIABLE_NAME,
+        ImmutableList.copyOf(Artifact.toExecPaths(objcProvider.getObjcLibraries())));
+    builder.addSequenceVariable(
+        CC_LIBRARY_EXEC_PATHS_VARIABLE_NAME,
+        ImmutableList.copyOf(Artifact.toExecPaths(objcProvider.getCcLibraries())));
+    builder.addSequenceVariable(
+        IMPORTED_LIBRARY_EXEC_PATHS_VARIABLE_NAME,
+        ImmutableList.copyOf(Artifact.toExecPaths(objcProvider.get(IMPORTED_LIBRARY))));
+  }
+}