Add ability to compile objc_binary targets with Swift sources.

* Swift sources whitelisted
* Swift compilation and module merging actions
* Swift stdlib copying into IPA action
* Special case for signing embedded swift stdlib dylibs during bundle signing
* Works with mixed ObjC/Swift sources
* Doesn't support working with dependencies from Swift code.
* Requires Xcode 6.3.1 for swift compiler and tooling.

--
MOS_MIGRATED_REVID=96141887

15 files changed, 386 insertions, 18 deletions

diff --git a/compile.sh b/compile.sh
index aaa4ba6e10..047d0e2b67 100755
--- a/compile.sh
+++ b/compile.sh
@@ -111,6 +111,8 @@ if [ $DO_TOOLS_COMPILATION ]; then
         tools/objc/precomp_actoolzip_deploy.jar
     bazel_bootstrap //src/tools/xcode-common/java/com/google/devtools/build/xcode/ibtoolzip:ibtoolzip_deploy.jar \
         tools/objc/precomp_ibtoolzip_deploy.jar
+    bazel_bootstrap //src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip:swiftstdlibtoolzip_deploy.jar \
+        tools/objc/precomp_swiftstdlibtoolzip_deploy.jar
     bazel_bootstrap //src/objc_tools/momczip:momczip_deploy.jar \
         tools/objc/precomp_momczip_deploy.jar
     bazel_bootstrap //src/objc_tools/bundlemerge:bundlemerge_deploy.jar \
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/Bundling.java b/src/main/java/com/google/devtools/build/lib/rules/objc/Bundling.java
index d3545fa7dd..b336096838 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/Bundling.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/Bundling.java
@@ -16,6 +16,7 @@ package com.google.devtools.build.lib.rules.objc;
 
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.ASSET_CATALOG;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.BUNDLE_FILE;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_SWIFT;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.IMPORTED_LIBRARY;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.LIBRARY;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.MERGE_ZIP;
@@ -166,6 +167,11 @@ final class Bundling {
       for (Artifact storyboard : objcProvider.get(STORYBOARD)) {
         mergeZipBuilder.add(intermediateArtifacts.compiledStoryboardZip(storyboard));
       }
+
+      if (objcProvider.is(USES_SWIFT)) {
+        mergeZipBuilder.add(intermediateArtifacts.swiftFrameworksFileZip());
+      }
+
       return mergeZipBuilder.build();
     }
 
@@ -434,7 +440,7 @@ final class Bundling {
   public NestedSet<Artifact> getBundleContentArtifacts() {
     return bundleContentArtifacts;
   }
-  
+
   /**
    * Returns primary bundle ID to use, can be null.
    */
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationArtifacts.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationArtifacts.java
index 5aac139e57..7d1377b5a5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationArtifacts.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CompilationArtifacts.java
@@ -16,6 +16,7 @@ package com.google.devtools.build.lib.rules.objc;
 
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
+import com.google.common.base.Predicate;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.actions.Artifact;
@@ -68,6 +69,7 @@ final class CompilationArtifacts {
   private final Iterable<Artifact> nonArcSrcs;
   private final Optional<Artifact> archive;
   private final Optional<Artifact> pchFile;
+  private final boolean hasSwiftSources;
 
   private CompilationArtifacts(
       Iterable<Artifact> srcs,
@@ -78,6 +80,12 @@ final class CompilationArtifacts {
     this.nonArcSrcs = Preconditions.checkNotNull(nonArcSrcs);
     this.archive = Preconditions.checkNotNull(archive);
     this.pchFile = Preconditions.checkNotNull(pchFile);
+    this.hasSwiftSources = Iterables.any(this.srcs, new Predicate<Artifact>() {
+      @Override
+      public boolean apply(Artifact artifact) {
+        return ObjcRuleClasses.SWIFT_SOURCES.matches(artifact.getExecPath());
+      }
+    });
   }
 
   public Iterable<Artifact> getSrcs() {
@@ -95,4 +103,11 @@ final class CompilationArtifacts {
   public Optional<Artifact> getPchFile() {
     return pchFile;
   }
+
+  /**
+   * Returns true if any of this target's srcs are Swift source files.
+   */
+  public boolean hasSwiftSources() {
+    return hasSwiftSources;
+  }
 }
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 bfd4b1819c..d6a5e8eab5 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
@@ -20,6 +20,7 @@ import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FORCE_LOAD_L
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FRAMEWORK_DIR;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FRAMEWORK_FILE;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_CPP;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_SWIFT;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.HEADER;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.IMPORTED_LIBRARY;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.INCLUDE;
@@ -32,12 +33,14 @@ import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.CLANG_PLU
 import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.DSYMUTIL;
 import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.NON_ARC_SRCS_TYPE;
 import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.SRCS_TYPE;
+import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.SWIFT;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Joiner;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.actions.Action;
 import com.google.devtools.build.lib.actions.Artifact;
@@ -146,17 +149,24 @@ final class CompilationSupport {
     for (Artifact sourceFile : compilationArtifacts.getSrcs()) {
       Artifact objFile = intermediateArtifacts.objFile(sourceFile);
       objFiles.add(objFile);
-      registerCompileAction(sourceFile, objFile, compilationArtifacts.getPchFile(),
-          objcProvider, intermediateArtifacts, ImmutableList.of("-fobjc-arc"),
-          isCodeCoverageEnabled);
+      if (ObjcRuleClasses.SWIFT_SOURCES.matches(sourceFile.getFilename())) {
+        registerSwiftCompileAction(sourceFile, objFile, intermediateArtifacts);
+      } else {
+        registerCompileAction(sourceFile, objFile, objcProvider, intermediateArtifacts,
+            compilationArtifacts, ImmutableList.of("-fobjc-arc"), isCodeCoverageEnabled);
+      }
     }
     for (Artifact nonArcSourceFile : compilationArtifacts.getNonArcSrcs()) {
       Artifact objFile = intermediateArtifacts.objFile(nonArcSourceFile);
       objFiles.add(objFile);
-      registerCompileAction(nonArcSourceFile, objFile, compilationArtifacts.getPchFile(),
-          objcProvider, intermediateArtifacts, ImmutableList.of("-fno-objc-arc"),
-          isCodeCoverageEnabled);
+      registerCompileAction(nonArcSourceFile, objFile, objcProvider, intermediateArtifacts,
+          compilationArtifacts, ImmutableList.of("-fno-objc-arc"), isCodeCoverageEnabled);
+    }
+
+    if (compilationArtifacts.hasSwiftSources()) {
+      registerSwiftModuleMergeAction(intermediateArtifacts, compilationArtifacts);
     }
+
     for (Artifact archive : compilationArtifacts.getArchive().asSet()) {
       registerArchiveActions(intermediateArtifacts, objFiles, archive);
     }
@@ -165,14 +175,15 @@ final class CompilationSupport {
   private void registerCompileAction(
       Artifact sourceFile,
       Artifact objFile,
-      Optional<Artifact> pchFile,
       ObjcProvider objcProvider,
       IntermediateArtifacts intermediateArtifacts,
+      CompilationArtifacts compilationArtifacts,
       Iterable<String> otherFlags,
       boolean isCodeCoverageEnabled) {
     ObjcConfiguration objcConfiguration = ObjcRuleClasses.objcConfiguration(ruleContext);
     ImmutableList.Builder<String> coverageFlags = new ImmutableList.Builder<>();
     ImmutableList.Builder<Artifact> gcnoFiles = new ImmutableList.Builder<>();
+    ImmutableList.Builder<Artifact> additionalInputs = new ImmutableList.Builder<>();
     if (isCodeCoverageEnabled) {
       coverageFlags.addAll(CLANG_COVERAGE_FLAGS);
       gcnoFiles.add(intermediateArtifacts.gcnoFile(sourceFile));
@@ -181,6 +192,14 @@ final class CompilationSupport {
     if (ObjcRuleClasses.CPP_SOURCES.matches(sourceFile.getExecPath())) {
       commandLine.add("-stdlib=libc++");
     }
+
+    if (compilationArtifacts.hasSwiftSources()) {
+      // Add the directory that contains merged TargetName-Swift.h header to search path, in case
+      // any of ObjC files use it.
+      commandLine.add("-I");
+      commandLine.addPath(intermediateArtifacts.swiftHeader().getExecPath().getParentDirectory());
+      additionalInputs.add(intermediateArtifacts.swiftHeader());
+    }
     commandLine
         .add(IosSdkCommands.compileFlagsForClang(objcConfiguration))
         .add(IosSdkCommands.commonLinkAndCompileFlagsForClang(
@@ -188,7 +207,7 @@ final class CompilationSupport {
         .add(objcConfiguration.getCoptsForCompilationMode())
         .addBeforeEachPath(
             "-iquote", ObjcCommon.userHeaderSearchPaths(ruleContext.getConfiguration()))
-        .addBeforeEachExecPath("-include", pchFile.asSet())
+        .addBeforeEachExecPath("-include", compilationArtifacts.getPchFile().asSet())
         .addBeforeEachPath("-I", objcProvider.get(INCLUDE))
         .add(otherFlags)
         .addFormatEach("-D%s", objcProvider.get(DEFINE))
@@ -204,11 +223,114 @@ final class CompilationSupport {
         .setExecutable(CLANG)
         .setCommandLine(commandLine.build())
         .addInput(sourceFile)
+        .addInputs(additionalInputs.build())
         .addOutput(objFile)
         .addOutputs(gcnoFiles.build())
         .addTransitiveInputs(objcProvider.get(HEADER))
         .addTransitiveInputs(objcProvider.get(FRAMEWORK_FILE))
-        .addInputs(pchFile.asSet())
+        .addInputs(compilationArtifacts.getPchFile().asSet())
+        .build(ruleContext));
+  }
+
+  /**
+   * Compiles a single swift file.
+   *
+   * @param sourceFile the artifact to compile
+   * @param objFile the resulting object artifact
+   */
+  private void registerSwiftCompileAction(
+      Artifact sourceFile,
+      Artifact objFile,
+      IntermediateArtifacts intermediateArtifacts) {
+    ObjcConfiguration objcConfiguration = ObjcRuleClasses.objcConfiguration(ruleContext);
+
+    // Compiling a single swift file requires knowledge of all of the other
+    // swift files in the same module. The primary file ({@code sourceFile}) is
+    // compiled to an object file, while the remaining files are used to resolve
+    // symbols (they behave like c/c++ headers in this context).
+    ImmutableSet.Builder<Artifact> otherSwiftSourcesBuilder = ImmutableSet.builder();
+    for (Artifact otherSourceFile : compilationArtifacts(ruleContext).getSrcs()) {
+      if (ObjcRuleClasses.SWIFT_SOURCES.matches(otherSourceFile.getFilename())
+          && otherSourceFile != sourceFile) {
+        otherSwiftSourcesBuilder.add(otherSourceFile);
+      }
+    }
+    ImmutableSet<Artifact> otherSwiftSources = otherSwiftSourcesBuilder.build();
+
+    CustomCommandLine.Builder commandLine = new CustomCommandLine.Builder()
+        .add("-frontend")
+        .add("-emit-object")
+        .add("-target").add(IosSdkCommands.swiftTarget(objcConfiguration))
+        .add("-sdk").add(IosSdkCommands.sdkDir(objcConfiguration))
+        .add("-enable-objc-interop");
+
+    if (objcConfiguration.generateDebugSymbols()) {
+      commandLine.add("-g");
+    }
+
+    commandLine
+      .add("-Onone")
+      .add("-module-name").add(getModuleName())
+      .add("-parse-as-library")
+      .addExecPath("-primary-file", sourceFile)
+      .addExecPaths(otherSwiftSources)
+      .addExecPath("-o", objFile)
+      .addExecPath("-emit-module-path", intermediateArtifacts.swiftModuleFile(sourceFile));
+
+    // Add all ObjC headers to the compiler, in case Swift code is calling into Objc
+    // TODO(bazel-team): This can be augmented by an explicit bridging header field in the rule.
+    commandLine.addBeforeEachExecPath("-import-objc-header", attributes.hdrs());
+
+    ruleContext.registerAction(ObjcRuleClasses.spawnOnDarwinActionBuilder()
+        .setMnemonic("SwiftCompile")
+        .setExecutable(SWIFT)
+        .setCommandLine(commandLine.build())
+        .addInput(sourceFile)
+        .addInputs(otherSwiftSources)
+        .addInputs(attributes.hdrs())
+        .addOutput(objFile)
+        .addOutput(intermediateArtifacts.swiftModuleFile(sourceFile))
+        .build(ruleContext));
+  }
+
+  /**
+   * Merges multiple .partial_swiftmodule files together. Also produces a swift header that can be
+   * used by Objective-C code.
+   */
+  private void registerSwiftModuleMergeAction(
+      IntermediateArtifacts intermediateArtifacts,
+      CompilationArtifacts compilationArtifacts) {
+    ObjcConfiguration objcConfiguration = ObjcRuleClasses.objcConfiguration(ruleContext);
+
+    ImmutableList.Builder<Artifact> moduleFiles = new ImmutableList.Builder<>();
+    for (Artifact src : compilationArtifacts.getSrcs()) {
+      if (ObjcRuleClasses.SWIFT_SOURCES.matches(src.getFilename())) {
+        moduleFiles.add(intermediateArtifacts.swiftModuleFile(src));
+      }
+    }
+
+    CustomCommandLine.Builder commandLine = new CustomCommandLine.Builder();
+    commandLine.add("-frontend");
+    commandLine.add("-emit-module");
+    commandLine.add("-sdk").add(IosSdkCommands.sdkDir(objcConfiguration));
+    commandLine.add("-target").add(IosSdkCommands.swiftTarget(objcConfiguration));
+    if (objcConfiguration.generateDebugSymbols()) {
+      commandLine.add("-g");
+    }
+
+    commandLine.add("-module-name").add(getModuleName());
+    commandLine.add("-parse-as-library");
+    commandLine.addExecPaths(moduleFiles.build());
+    commandLine.addExecPath("-o", intermediateArtifacts.swiftModule());
+    commandLine.addExecPath("-emit-objc-header-path", intermediateArtifacts.swiftHeader());
+
+    ruleContext.registerAction(ObjcRuleClasses.spawnOnDarwinActionBuilder()
+        .setMnemonic("SwiftModuleMerge")
+        .setExecutable(SWIFT)
+        .setCommandLine(commandLine.build())
+        .addInputs(moduleFiles.build())
+        .addOutput(intermediateArtifacts.swiftModule())
+        .addOutput(intermediateArtifacts.swiftHeader())
         .build(ruleContext));
   }
 
@@ -345,6 +467,13 @@ final class CompilationSupport {
       commandLine.add(LINKER_COVERAGE_FLAGS);
     }
 
+    if (objcProvider.is(USES_SWIFT)) {
+      commandLine
+          .add("-L").add(IosSdkCommands.swiftLibDir(objcConfiguration))
+          .add("-Xlinker").add("-rpath")
+          .add("-Xlinker").add("@executable_path/Frameworks");
+    }
+
     // Call to dsymutil for debug symbol generation must happen in the link action.
     // All debug symbol information is encoded in object files inside archive files. To generate
     // the debug symbol bundle, dsymutil will look inside the linked binary for the encoded
@@ -565,4 +694,11 @@ final class CompilationSupport {
     // TODO(bazel-team): Throw instead of returning null?
     return str.endsWith(suffix) ? str.substring(0, str.length() - suffix.length()) : null;
   }
+
+  /**
+   * Returns the name of Swift module for this target.
+   */
+  private String getModuleName() {
+    return ruleContext.getLabel().getName();
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IntermediateArtifacts.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IntermediateArtifacts.java
index 9e1372e8d4..4af59d6ad5 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IntermediateArtifacts.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IntermediateArtifacts.java
@@ -183,6 +183,28 @@ final class IntermediateArtifacts {
   }
 
   /**
+   * The swift module produced by compiling the {@code source} artifact.
+   */
+  public Artifact swiftModuleFile(Artifact source) {
+    return analysisEnvironment.getDerivedArtifact(inUniqueObjsDir(source, ".partial_swiftmodule"),
+        binDirectory);
+  }
+
+  /**
+   * Integrated swift module for this target.
+   */
+  public Artifact swiftModule() {
+    return appendExtension(".swiftmodule");
+  }
+
+  /**
+   * Integrated swift header for this target.
+   */
+  public Artifact swiftHeader() {
+    return appendExtension("-Swift.h");
+  }
+
+  /**
    * The artifact for the .gcno file that should be generated when compiling the {@code source}
    * artifact.
    */
@@ -236,6 +258,14 @@ final class IntermediateArtifacts {
   }
 
   /**
+   * Returns the artifact which is the output of running swift-stdlib-tool and copying resulting
+   * dylibs.
+   */
+  public Artifact swiftFrameworksFileZip() {
+    return appendExtension(".swiftstdlib.zip");
+  }
+
+  /**
    * Debug symbol plist generated for a linked binary.
    */
   public Artifact dsymPlist() {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosSdkCommands.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosSdkCommands.java
index 32c24c1395..b788f7c0e0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosSdkCommands.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosSdkCommands.java
@@ -84,6 +84,28 @@ public class IosSdkCommands {
     return platformDir(configuration) + "/Developer/Library/Frameworks";
   }
 
+  /**
+   * Returns swift libraries path.
+   */
+  public static String swiftLibDir(ObjcConfiguration configuration) {
+    return DEVELOPER_DIR + "/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/"
+        + swiftPlatform(configuration);
+  }
+
+  /**
+   * Returns a platform name string suitable for use in Swift tools.
+   */
+  public static String swiftPlatform(ObjcConfiguration configuration) {
+    return getPlatformPlistName(configuration).toLowerCase();
+  }
+
+  /**
+   * Returns the target string for swift compiler. For example, "x86_64-apple-ios8.2"
+   */
+  public static String swiftTarget(ObjcConfiguration configuration) {
+    return configuration.getIosCpu() + "-apple-" + "ios" + configuration.getIosSdkVersion();
+  }
+
   private static Iterable<PathFragment> uniqueParentDirectories(Iterable<PathFragment> paths) {
     ImmutableSet.Builder<PathFragment> parents = new ImmutableSet.Builder<>();
     for (PathFragment path : paths) {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
index e311bc3473..3b317ab8dd 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
@@ -26,6 +26,7 @@ import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FORCE_LOAD_L
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FRAMEWORK_DIR;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FRAMEWORK_FILE;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_CPP;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_SWIFT;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.GCNO;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.GENERAL_RESOURCE_FILE;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.HEADER;
@@ -455,13 +456,20 @@ public final class ObjcCommon {
         }
 
         boolean usesCpp = false;
+        boolean usesSwift = false;
         for (Artifact sourceFile :
             Iterables.concat(artifacts.getSrcs(), artifacts.getNonArcSrcs())) {
           usesCpp = usesCpp || ObjcRuleClasses.CPP_SOURCES.matches(sourceFile.getExecPath());
+          usesSwift = usesSwift || ObjcRuleClasses.SWIFT_SOURCES.matches(sourceFile.getExecPath());
         }
+
         if (usesCpp) {
           objcProvider.add(FLAG, USES_CPP);
         }
+
+        if (usesSwift) {
+          objcProvider.add(FLAG, USES_SWIFT);
+        }
       }
 
       if (alwayslink) {
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 e2fc6e9363..92fce30111 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
@@ -199,7 +199,13 @@ public final class ObjcProvider implements TransitiveInfoProvider {
      * Indicates that C++ (or Objective-C++) is used in any source file. This affects how the linker
      * is invoked.
     */
-    USES_CPP;
+    USES_CPP,
+
+    /**
+     * Indicates that Swift source files are present. This affects bundling, compiling and linking
+     * actions.
+     */
+    USES_SWIFT
   }
 
   private final ImmutableMap<Key<?>, NestedSet<?>> items;
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
index dec8cc582c..bd2ecc6566 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
@@ -61,10 +61,13 @@ public class ObjcRuleClasses {
       IosSdkCommands.DEVELOPER_DIR + "/Toolchains/XcodeDefault.xctoolchain/usr/bin";
   static final PathFragment CLANG = new PathFragment(BIN_DIR + "/clang");
   static final PathFragment CLANG_PLUSPLUS = new PathFragment(BIN_DIR + "/clang++");
+  static final PathFragment SWIFT = new PathFragment(BIN_DIR + "/swift");
   static final PathFragment LIBTOOL = new PathFragment(BIN_DIR + "/libtool");
   static final PathFragment DSYMUTIL = new PathFragment(BIN_DIR + "/dsymutil");
   static final PathFragment LIPO = new PathFragment(BIN_DIR + "/lipo");
   static final PathFragment IBTOOL = new PathFragment(IosSdkCommands.IBTOOL_PATH);
+  static final PathFragment SWIFT_STDLIB_TOOL = new PathFragment(BIN_DIR + "/swift-stdlib-tool");
+
   private static final PathFragment JAVA = new PathFragment("/usr/bin/java");
 
   private ObjcRuleClasses() {
@@ -312,9 +315,11 @@ public class ObjcRuleClasses {
    */
   static final FileType CPP_SOURCES = FileType.of(".cc", ".cpp", ".mm", ".cxx", ".C");
 
+  static final FileType SWIFT_SOURCES = FileType.of(".swift");
+
   private static final FileType NON_CPP_SOURCES = FileType.of(".m", ".c");
 
-  static final FileTypeSet SRCS_TYPE = FileTypeSet.of(NON_CPP_SOURCES, CPP_SOURCES);
+  static final FileTypeSet SRCS_TYPE = FileTypeSet.of(NON_CPP_SOURCES, CPP_SOURCES, SWIFT_SOURCES);
 
   static final FileTypeSet NON_ARC_SRCS_TYPE = FileTypeSet.of(FileType.of(".m", ".mm"));
 
@@ -452,6 +457,8 @@ public class ObjcRuleClasses {
               .value(env.getLabel("//tools/objc:actoolzip_deploy.jar")))
           .add(attr("$ibtoolzip_deploy", LABEL).cfg(HOST)
               .value(env.getLabel("//tools/objc:ibtoolzip_deploy.jar")))
+          .add(attr("$swiftstdlibtoolzip_deploy", LABEL).cfg(HOST)
+              .value(env.getLabel("//tools/objc:swiftstdlibtoolzip_deploy.jar")))
           .build();
     }
     @Override
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
index f403daa7db..e10dee00f6 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
@@ -16,6 +16,7 @@ package com.google.devtools.build.lib.rules.objc;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.devtools.build.lib.packages.ImplicitOutputsFunction.fromTemplates;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.USES_SWIFT;
 import static com.google.devtools.build.lib.rules.objc.TargetDeviceFamily.UI_DEVICE_FAMILY_VALUES;
 
 import com.google.common.annotations.VisibleForTesting;
@@ -203,6 +204,7 @@ public final class ReleaseBundlingSupport {
 
     registerCombineArchitecturesAction();
     registerTransformAndCopyBreakpadFilesAction();
+    registerSwiftStdlibActionsIfNecessary();
 
     ObjcConfiguration objcConfiguration = ObjcRuleClasses.objcConfiguration(ruleContext);
     Artifact ipaOutput = ruleContext.getImplicitOutputArtifact(IPA);
@@ -505,23 +507,38 @@ public final class ReleaseBundlingSupport {
   private ReleaseBundlingSupport registerSignBundleAction(
       Artifact entitlements, Artifact ipaOutput, Artifact ipaUnsigned) {
     // TODO(bazel-team): Support variable substitution
+
+    ImmutableList.Builder<String> dirsToSign = new ImmutableList.Builder<>();
+
+    // Explicitly sign Swift frameworks. Unfortunately --deep option on codesign doesn't do this
+    // automatically.
+    // The order here is important. The innermost code must singed first.
+    if (objcProvider.is(USES_SWIFT)) {
+      dirsToSign.add(bundling.getBundleDir() + "/Frameworks/*");
+    }
+    dirsToSign.add(bundling.getBundleDir());
+
+    StringBuilder codesignCommandLineBuilder = new StringBuilder();
+    for (String dir : dirsToSign.build()) {
+      codesignCommandLineBuilder
+          .append(codesignCommand(attributes.provisioningProfile(), entitlements, "${t}/" + dir))
+          .append(" && ");
+    }
+
     ruleContext.registerAction(ObjcRuleClasses.spawnOnDarwinActionBuilder()
         .setMnemonic("IosSignBundle")
         .setProgressMessage("Signing iOS bundle: " + ruleContext.getLabel())
         .setExecutable(new PathFragment("/bin/bash"))
         .addArgument("-c")
-        // TODO(bazel-team): Support --resource-rules for resources
+        // TODO(bazel-team): Support nested code signing.
         .addArgument("set -e && "
             + "t=$(mktemp -d -t signing_intermediate) && "
             // Get an absolute path since we need to cd into the temp directory for zip.
             + "signed_ipa=${PWD}/" + ipaOutput.getExecPathString() + " && "
             + "unzip -qq " + ipaUnsigned.getExecPathString() + " -d ${t} && "
-            + codesignCommand(
-                attributes.provisioningProfile(),
-                entitlements,
-                "${t}/" + bundling.getBundleDir())
+            + codesignCommandLineBuilder.toString()
             // Using zip since we need to preserve permissions
-            + " && cd \"${t}\" && /usr/bin/zip -q -r \"${signed_ipa}\" .")
+            + "cd \"${t}\" && /usr/bin/zip -q -r \"${signed_ipa}\" .")
         .addInput(ipaUnsigned)
         .addInput(attributes.provisioningProfile())
         .addInput(entitlements)
@@ -668,6 +685,31 @@ public final class ReleaseBundlingSupport {
         .build(ruleContext));
   }
 
+  /**
+   * Registers an action to copy Swift standard library dylibs into app bundle.
+   */
+  private void registerSwiftStdlibActionsIfNecessary() {
+    if (!objcProvider.is(USES_SWIFT)) {
+      return;
+    }
+
+    ObjcConfiguration objcConfiguration = ObjcRuleClasses.objcConfiguration(ruleContext);
+
+    CustomCommandLine.Builder commandLine = CustomCommandLine.builder()
+        .addPath(intermediateArtifacts.swiftFrameworksFileZip().getExecPath())
+        .add("Frameworks")
+        .addPath(ObjcRuleClasses.SWIFT_STDLIB_TOOL)
+        .add("--platform").add(IosSdkCommands.swiftPlatform(objcConfiguration))
+        .addExecPath("--scan-executable", intermediateArtifacts.singleArchitectureBinary());
+
+    ruleContext.registerAction(
+        ObjcRuleClasses.spawnJavaOnDarwinActionBuilder(attributes.swiftStdlibToolDeployJar())
+            .setMnemonic("SwiftStdlibCopy")
+            .setCommandLine(commandLine.build())
+            .addOutput(intermediateArtifacts.swiftFrameworksFileZip())
+            .addInput(intermediateArtifacts.singleArchitectureBinary())
+            .build(ruleContext));
+  }
 
   private String extractPlistCommand(Artifact provisioningProfile) {
     return "security cms -D -i " + ShellUtils.shellEscape(provisioningProfile.getExecPathString());
@@ -757,6 +799,13 @@ public final class ReleaseBundlingSupport {
           ruleContext.getPrerequisiteArtifact("$runner_script_template", Mode.HOST));
     }
 
+    /**
+     * Returns the location of the swiftstdlibtoolzip deploy jar.
+     */
+    Artifact swiftStdlibToolDeployJar() {
+      return ruleContext.getPrerequisiteArtifact("$swiftstdlibtoolzip_deploy", Mode.HOST);
+    }
+
     String bundleId() {
       return checkNotNull(stringAttribute("bundle_id"));
     }
diff --git a/src/tools/xcode-common/BUILD b/src/tools/xcode-common/BUILD
index b34518bb66..187e8c1dfe 100644
--- a/src/tools/xcode-common/BUILD
+++ b/src/tools/xcode-common/BUILD
@@ -6,6 +6,7 @@ filegroup(
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/actoolzip:srcs",
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/common:srcs",
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/ibtoolzip:srcs",
+        "//src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip:srcs",
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/util:srcs",
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/zip:srcs",
         "//src/tools/xcode-common/java/com/google/devtools/build/xcode/zippingoutput:srcs",
diff --git a/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/BUILD b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/BUILD
new file mode 100644
index 0000000000..b42968804a
--- /dev/null
+++ b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/BUILD
@@ -0,0 +1,17 @@
+package(default_visibility = ["//src:__subpackages__"])
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]),
+)
+
+java_binary(
+    name = "swiftstdlibtoolzip",
+    srcs = ["SwiftStdlibToolZip.java"],
+    main_class = "com.google.devtools.build.xcode.swiftstdlibtoolzip.SwiftStdlibToolZip",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//src/tools/xcode-common/java/com/google/devtools/build/xcode/zippingoutput",
+        "//third_party:guava",
+    ],
+)
diff --git a/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/README b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/README
new file mode 100644
index 0000000000..0c8b3f082d
--- /dev/null
+++ b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/README
@@ -0,0 +1,4 @@
+swiftstdlibtoolzip runs swift-stdlib-tool, which scans executables and copies required Swift
+framework dylibs to the specified path, then zips up the output for further bundle merging.
+
+swift-stdlib-tool only runs on Darwin, so swiftstdlibtoolzip only runs on Darwin.
diff --git a/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/SwiftStdlibToolZip.java b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/SwiftStdlibToolZip.java
new file mode 100644
index 0000000000..2043a08fd3
--- /dev/null
+++ b/src/tools/xcode-common/java/com/google/devtools/build/xcode/swiftstdlibtoolzip/SwiftStdlibToolZip.java
@@ -0,0 +1,59 @@
+// Copyright 2015 Google Inc. 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.xcode.swiftstdlibtoolzip;
+
+import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.xcode.zippingoutput.Arguments;
+import com.google.devtools.build.xcode.zippingoutput.Wrapper;
+import com.google.devtools.build.xcode.zippingoutput.Wrappers;
+
+import java.io.IOException;
+
+/**
+ * A tool which wraps swift-stdlib-tool by running and zipping its output. See {@link Wrapper} for
+ * more information.
+ */
+public class SwiftStdlibToolZip implements Wrapper {
+
+  @Override
+  public String name() {
+    return "SwiftStdlibToolZip";
+  }
+
+  @Override
+  public String subtoolName() {
+    return "swift-stdlib-tool";
+  }
+
+  @Override
+  public Iterable<String> subCommand(Arguments arguments, String outputDirectory) {
+    return new ImmutableList.Builder<String>()
+        .add(arguments.subtoolCmd())
+        .addAll(arguments.subtoolExtraArgs())
+        .add("--copy")
+        .add("--verbose")
+        .add("--destination").add(outputDirectory)
+        .build();
+  }
+
+  @Override
+  public boolean outputDirectoryMustExist() {
+    return true;
+  }
+
+  public static void main(String[] args) throws IOException, InterruptedException {
+    Wrappers.executePipingOutput(args, new SwiftStdlibToolZip());
+  }
+}
diff --git a/tools/objc/BUILD b/tools/objc/BUILD
index 9ab7180907..8b27ebe1d1 100644
--- a/tools/objc/BUILD
+++ b/tools/objc/BUILD
@@ -39,6 +39,12 @@ java_binary(
     main_class = "com.google.devtools.build.xcode.xcodegen.XcodeGen",
 )
 
+java_binary(
+    name = "swiftstdlibtoolzip",
+    srcs = [":precomp_xcodegen_deploy.jar"],
+    main_class = "com.google.devtools.build.xcode.swiftstdlibtoolzip.SwiftStdlibToolZip",
+)
+
 filegroup(
     name = "srcs",
     srcs = glob(["**"]),