Introduce --apple_crosstool_top, which sets the crosstool for sources…

… in objc_*/apple_*/ios_* targets and their dependencies.

--
PiperOrigin-RevId: 142702735
MOS_MIGRATED_REVID=142702735

src/main/java/com/google/devtools/build/lib/bazel/rules/BazelConfigurationCollection.java

@@ -19,6 +19,7 @@
 import com.google.common.collect.HashBasedTable;
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Iterables;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Table;
 import com.google.devtools.build.lib.analysis.ConfigurationCollectionFactory;
@@ -34,7 +35,10 @@
 import com.google.devtools.build.lib.packages.Attribute.ConfigurationTransition;
 import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
 import com.google.devtools.build.lib.packages.Attribute.Transition;
+import com.google.devtools.build.lib.packages.Target;
+import com.google.devtools.build.lib.rules.apple.AppleConfiguration;
 import com.google.devtools.build.lib.rules.cpp.CppRuleClasses.LipoTransition;
+import com.google.devtools.build.lib.rules.objc.AppleCrosstoolTransition;
 import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Set;
@@ -104,6 +108,17 @@ protected Transition getDynamicTransition(Transition configurationTransition) {
         return super.getDynamicTransition(configurationTransition);
       }
     }
+
+    @Override
+    public BuildConfiguration toplevelConfigurationHook(Target toTarget) {
+      return (AppleConfiguration.APPLE_CROSSTOOL_RULE_CLASSES
+          .contains(toTarget.getAssociatedRule().getRuleClass()))
+          ? Iterables.getOnlyElement(
+              configuration
+                  .getTransitions()
+                  .getSplitConfigurations(AppleCrosstoolTransition.APPLE_CROSSTOOL_TRANSITION))
+          : configuration;
+    } 
   }
 
   @Override

src/main/java/com/google/devtools/build/lib/rules/apple/AppleCommandLineOptions.java

@@ -136,6 +136,16 @@ public class AppleCommandLineOptions extends FragmentOptions {
       help = "Specifies to target CPU of iOS compilation.")
   public String iosCpu;
 
+  @Option(
+      name = "apple_crosstool_top",
+      defaultValue = "@bazel_tools//tools/cpp:toolchain",
+      category = "version",
+      converter = LabelConverter.class,
+      help = "The label of the crosstool package to be used in Apple and Objc rules and their"
+            + " dependencies."
+    )
+  public Label appleCrosstoolTop;  
+
   @Option(name = "apple_platform_type",
       defaultValue = "IOS",
       category = "undocumented",

src/main/java/com/google/devtools/build/lib/rules/apple/AppleConfiguration.java

@@ -65,8 +65,20 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    **/
   public static final String APPLE_SDK_PLATFORM_ENV_NAME = "APPLE_SDK_PLATFORM";
 
-  private static final DottedVersion MINIMUM_BITCODE_XCODE_VERSION = DottedVersion.fromString("7");
+  /**
+   * Rule classes that need a top level transition to the apple crosstool.
+   * 
+   * <p>This list must not contain any rule classes that require some other split transition, as
+   * that transition would be suppressed by the top level transition to the apple crosstool. For
+   * example, if "apple_binary" were in this list, the multi-arch transition would not occur.
+   */
+  public static final ImmutableList<String> APPLE_CROSSTOOL_RULE_CLASSES = ImmutableList.of(
+      "objc_library",
+      "objc_binary",
+      "experimental_objc_library"); 
 
+  private static final DottedVersion MINIMUM_BITCODE_XCODE_VERSION = DottedVersion.fromString("7");
+
   private final DottedVersion iosSdkVersion;
   private final DottedVersion iosMinimumOs;
   private final DottedVersion watchosSdkVersion;
@@ -628,5 +640,7 @@ public enum ConfigurationDistinguisher {
     APPLEBIN_WATCHOS,
     /** Distinguisher for {@code apple_binary} rule with "tvos" platform_type. */
     APPLEBIN_TVOS,
+    /** Distinguisher for the apple crosstool configuration. */
+    APPLE_CROSSTOOL,
   }
 }

src/main/java/com/google/devtools/build/lib/rules/objc/AppleCrosstoolTransition.java

@@ -0,0 +1,82 @@
+// 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 com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
+import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
+import com.google.devtools.build.lib.rules.apple.AppleCommandLineOptions;
+import com.google.devtools.build.lib.rules.apple.AppleConfiguration.ConfigurationDistinguisher;
+import com.google.devtools.build.lib.rules.cpp.CppOptions;
+import java.util.List;
+
+/**
+ * Transition that produces a configuration that causes c++ toolchain selection to use the
+ * CROSSTOOL given in apple_crosstool_top.
+ */
+public class AppleCrosstoolTransition implements SplitTransition<BuildOptions> {
+
+  /**
+   * A singleton instance of AppleCrosstoolTransition.
+   */
+  public static final SplitTransition<BuildOptions> APPLE_CROSSTOOL_TRANSITION =
+      new AppleCrosstoolTransition();
+
+  @Override
+  public boolean defaultsToSelf() {
+    return true;
+  }
+
+  @Override
+  public List<BuildOptions> split(BuildOptions buildOptions) {
+    BuildOptions result = buildOptions.clone();
+    result.get(AppleCommandLineOptions.class).configurationDistinguisher =
+        ConfigurationDistinguisher.APPLE_CROSSTOOL;
+
+
+    // TODO(b/29355778): Once ios_cpu is retired, introduce another top-level flag (perhaps
+    // --apple_cpu) for toolchain selection in top-level consuming rules.
+    String cpu = "ios_" + buildOptions.get(AppleCommandLineOptions.class).iosCpu;
+    setAppleCrosstoolTransitionConfiguration(buildOptions, result, cpu);
+    return ImmutableList.of(result);
+  }
+
+  /**
+   * Sets configuration fields required for a transition that uses apple_crosstool_top in place of
+   * the default CROSSTOOL.
+   *
+   * @param from options from the originating configuration
+   * @param to options for the destination configuration. This instance will be modified
+   *     to so the destination configuration uses the apple crosstool
+   * @param cpu {@code --cpu} value for toolchain selection in the destination configuration
+   */
+  public static void setAppleCrosstoolTransitionConfiguration(BuildOptions from,
+      BuildOptions to, String cpu) {
+    to.get(BuildConfiguration.Options.class).cpu = cpu;
+    to.get(CppOptions.class).crosstoolTop =
+        from.get(AppleCommandLineOptions.class).appleCrosstoolTop; 
+
+    // --compiler = "compiler" for all OSX toolchains.  We do not support asan/tsan, cfi, etc. on
+    // darwin.
+    to.get(CppOptions.class).cppCompiler = "compiler";
+
+    // OSX toolchains always use the runtime of the platform they are targeting (i.e. we do not
+    // support custom production environments).
+    to.get(CppOptions.class).libcTop = null;
+    to.get(CppOptions.class).glibc = null; 
+  }
+
+}

src/main/java/com/google/devtools/build/lib/rules/objc/MultiArchSplitTransitionProvider.java

@@ -21,7 +21,6 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.analysis.RuleContext;
-import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
 import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
 import com.google.devtools.build.lib.packages.Attribute.SplitTransitionProvider;
@@ -32,7 +31,6 @@
 import com.google.devtools.build.lib.rules.apple.AppleConfiguration.ConfigurationDistinguisher;
 import com.google.devtools.build.lib.rules.apple.Platform.PlatformType;
 import com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.MultiArchPlatformRule;
-
 import java.util.List;
 
 /**
@@ -161,17 +159,20 @@ public final List<BuildOptions> split(BuildOptions buildOptions) {
 
         splitOptions.get(AppleCommandLineOptions.class).applePlatformType = platformType;
         splitOptions.get(AppleCommandLineOptions.class).appleSplitCpu = cpu;
-        // Set for backwards compatibility with rules that depend on this flag, even when
-        // ios is not the platform type.
-        // TODO(b/28958783): Clean this up.
-        splitOptions.get(AppleCommandLineOptions.class).iosCpu = cpu;
         if (splitOptions.get(ObjcCommandLineOptions.class).enableCcDeps) {
           // Only set the (CC-compilation) CPU for dependencies if explicitly required by the user.
           // This helps users of the iOS rules who do not depend on CC rules as these CPU values
           // require additional flags to work (e.g. a custom crosstool) which now only need to be
           // set if this feature is explicitly requested.
-          splitOptions.get(BuildConfiguration.Options.class).cpu =
-              String.format("%s_%s", platformType, cpu);
+          String platformCpu = String.format("%s_%s", platformType, cpu);
+          AppleCrosstoolTransition.setAppleCrosstoolTransitionConfiguration(buildOptions,
+              splitOptions, platformCpu);
+        } else {
+          // If the new configuration does not use the apple crosstool, then it needs ios_cpu to be
+          // to decide architecture.
+          // TODO(b/29355778, b/28403953): Use a crosstool for any apple rule, and remove this
+          // "else" clause.  Deprecate ios_cpu.
+          splitOptions.get(AppleCommandLineOptions.class).iosCpu = cpu;
         }
         splitOptions.get(AppleCommandLineOptions.class).configurationDistinguisher =
             configurationDistinguisher;
@@ -185,4 +186,4 @@ public boolean defaultsToSelf() {
       return true;
     }
   }
-}
+}

src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java

@@ -251,7 +251,8 @@ public class ObjcCommandLineOptions extends FragmentOptions {
   public List<SplitTransition<BuildOptions>> getPotentialSplitTransitions() {
     return ImmutableList.<SplitTransition<BuildOptions>>builder().add(
             IosApplication.SPLIT_ARCH_TRANSITION, IosExtension.MINIMUM_OS_AND_SPLIT_ARCH_TRANSITION,
-            AppleWatch1Extension.MINIMUM_OS_AND_SPLIT_ARCH_TRANSITION)
+            AppleWatch1Extension.MINIMUM_OS_AND_SPLIT_ARCH_TRANSITION,
+            AppleCrosstoolTransition.APPLE_CROSSTOOL_TRANSITION)
         .addAll(MultiArchSplitTransitionProvider.getPotentialSplitTransitions())
         .build();
   }

src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java

@@ -47,7 +47,6 @@
 import com.google.devtools.build.lib.analysis.actions.SymlinkAction;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction.Substitution;
-import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
 import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
@@ -1344,7 +1343,7 @@ public final List<BuildOptions> split(BuildOptions buildOptions) {
       ImmutableList.Builder<BuildOptions> splitBuildOptions = ImmutableList.builder();
       for (String iosCpu : iosMultiCpus) {
         BuildOptions splitOptions = buildOptions.clone();
-        setArchitectureOptions(splitOptions, iosCpu);
+        setArchitectureOptions(splitOptions, buildOptions, iosCpu);
         setAdditionalOptions(splitOptions, buildOptions);
         splitOptions.get(AppleCommandLineOptions.class).configurationDistinguisher =
             getConfigurationDistinguisher();
@@ -1372,17 +1371,19 @@ protected ImmutableList<BuildOptions> defaultOptions(BuildOptions originalOption
      */
     protected void setAdditionalOptions(BuildOptions splitOptions, BuildOptions originalOptions) {}
 
-    private void setArchitectureOptions(BuildOptions splitOptions, String iosCpu) {
+    private static void setArchitectureOptions(BuildOptions splitOptions, 
+        BuildOptions originalOptions, String iosCpu) {
       splitOptions.get(AppleCommandLineOptions.class).applePlatformType = PlatformType.IOS;
       splitOptions.get(AppleCommandLineOptions.class).appleSplitCpu = iosCpu;
       splitOptions.get(AppleCommandLineOptions.class).iosCpu = iosCpu;
-      if (splitOptions.get(ObjcCommandLineOptions.class).enableCcDeps) {
+     if (splitOptions.get(ObjcCommandLineOptions.class).enableCcDeps) {
         // Only set the (CC-compilation) CPU for dependencies if explicitly required by the user.
         // This helps users of the iOS rules who do not depend on CC rules as these CPU values
         // require additional flags to work (e.g. a custom crosstool) which now only need to be set
         // if this feature is explicitly requested.
-        splitOptions.get(BuildConfiguration.Options.class).cpu = "ios_" + iosCpu;
-      }
+        AppleCrosstoolTransition.setAppleCrosstoolTransitionConfiguration(originalOptions,
+            splitOptions, "ios_" + iosCpu);
+     }
     }
 
     @Override

src/test/java/com/google/devtools/build/lib/analysis/mock/MOCK_CROSSTOOL

@@ -20,6 +20,10 @@ default_toolchain {
   cpu: "darwin"
   toolchain_identifier: "local_darwin"
 }
+default_toolchain {
+  cpu: "ios_x86_64"
+  toolchain_identifier: "local_ios"
+}
 default_toolchain {
   cpu: "x64_windows"
   toolchain_identifier: "local_windows_msys64"
@@ -354,6 +358,52 @@ toolchain {
   supports_interface_shared_objects: true
 }
 
+# Stub crosstool to allow construction of apple crosstool configuration in a
+# static configuration set.
+# TODO(b/33804121): Remove this once dynamic configurations are in place.
+toolchain {
+  toolchain_identifier: "local_ios"
+
+  host_system_name: "local"
+  target_system_name: "local"
+  target_cpu: "ios_x86_64"
+  target_libc: "ios"
+  compiler: "compiler"
+  linking_mode_flags { mode: DYNAMIC }
+
+  abi_version: "local"
+  abi_libc_version: "local"
+
+  tool_path { name: "ar" path: "/usr/bin/libtool" }
+  tool_path { name: "compat-ld" path: "/usr/bin/ld" }
+  tool_path { name: "cpp" path: "/usr/bin/cpp" }
+  tool_path { name: "dwp" path: "/usr/bin/dwp" }
+  tool_path { name: "gcc" path: "/usr/bin/gcc" }
+  tool_path { name: "gcov" path: "/usr/bin/gcov" }
+  tool_path { name: "ld" path: "/usr/bin/ld" }
+  tool_path { name: "nm" path: "/usr/bin/nm" }
+  tool_path { name: "objcopy" path: "/usr/bin/objcopy" }
+  tool_path { name: "objdump" path: "/usr/bin/objdump" }
+  tool_path { name: "strip" path: "/usr/bin/strip" }
+
+  needsPic: false
+
+  builtin_sysroot: ""
+  cxx_flag: "-std=c++0x"
+  ar_flag: "-static"
+  ar_flag: "-s"
+  ar_flag: "-o"
+  linker_flag: "-lstdc++"
+  cxx_builtin_include_directory: "/usr/include"
+  cxx_builtin_include_directory: "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain"
+  cxx_builtin_include_directory: "/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs"
+  cxx_builtin_include_directory: "/opt/local/include"
+  cxx_builtin_include_directory: "/Library/Developer/CommandLineTools"
+  objcopy_embed_flag: "-I"
+  objcopy_embed_flag: "binary"
+  supports_interface_shared_objects: true
+}
+
 toolchain {
   toolchain_identifier: "local_windows_mingw"
 

src/test/java/com/google/devtools/build/lib/packages/util/BazelMockCcSupport.java

@@ -87,6 +87,7 @@ public void setup(MockToolsConfig config) throws IOException {
         "      'k8|compiler': ':cc-compiler-k8',",
         "      'piii|compiler': ':cc-compiler-piii',",
         "      'darwin|compiler': ':cc-compiler-darwin',",
+        "      'ios_x86_64|compiler': ':cc-compiler-ios_x86_64',",
         "      'armeabi-v7a|compiler': ':cc-compiler-armeabi-v7a',",
         "      'x64_windows|windows_msys64': ':cc-compiler-x64_windows',",
         "      'ppc|compiler': ':cc-compiler-ppc',",
@@ -116,6 +117,13 @@ public void setup(MockToolsConfig config) throws IOException {
         "    module_map = 'crosstool.cppmap', supports_header_parsing = 1,",
         "    objcopy_files = ':empty', static_runtime_libs = [':empty'], strip_files = ':empty',",
         ")",
+        "cc_toolchain(name = 'cc-compiler-ios_x86_64', all_files = ':empty', ",
+        "    compiler_files = ':empty',",
+        "    cpu = 'local', dwp_files = ':empty', dynamic_runtime_libs = [':empty'], ",
+        "    linker_files = ':empty',",
+        "    module_map = 'crosstool.cppmap', supports_header_parsing = 1,",
+        "    objcopy_files = ':empty', static_runtime_libs = [':empty'], strip_files = ':empty',",
+        ")", 
         "cc_toolchain(name = 'cc-compiler-armeabi-v7a', all_files = ':empty', ",
         "    compiler_files = ':empty',",
         "    cpu = 'local', dwp_files = ':empty', dynamic_runtime_libs = [':empty'], ",

src/test/shell/bazel/apple/bazel_apple_test.sh

@@ -753,8 +753,8 @@ EOF
 
   bazel build --verbose_failures --xcode_version=$XCODE_VERSION -s \
       //ios:bin >$TEST_log 2>&1 || fail "should build"
-  expect_log "-Xlinker -add_ast_path -Xlinker bazel-out/local-fastbuild/genfiles/ios/dep/_objs/ios_dep.swiftmodule"
-  expect_log "-Xlinker -add_ast_path -Xlinker bazel-out/local-fastbuild/genfiles/ios/swift_lib/_objs/ios_swift_lib.swiftmodule"
+  expect_log "-Xlinker -add_ast_path -Xlinker bazel-out/apple_crosstool-ios_x86_64-fastbuild/genfiles/ios/dep/_objs/ios_dep.swiftmodule"
+  expect_log "-Xlinker -add_ast_path -Xlinker bazel-out/apple_crosstool-ios_x86_64-fastbuild/genfiles/ios/swift_lib/_objs/ios_swift_lib.swiftmodule"
 }
 
 function test_swiftc_script_mode() {

src/test/shell/bazel/apple/bazel_objc_test.sh

@@ -207,9 +207,9 @@ EOF
   # Dec 31 1969 or Jan 1 1970 -- either is fine.
   # We would use 'date' here, but the format is slightly different (Jan 1 vs.
   # Jan 01).
-  ar -tv bazel-bin/objclib/libobjclib.a \
+  ar -tv bazel-out/apple_crosstool-ios_x86_64-fastbuild/bin/objclib/libobjclib.a \
       | grep "mysrc" | grep "Dec 31" | grep "1969" \
-      || ar -tv bazel-bin/objclib/libobjclib.a \
+      || ar -tv bazel-out/apple_crosstool-ios_x86_64-fastbuild/bin/objclib/libobjclib.a \
       | grep "mysrc" | grep "Jan  1" | grep "1970" || \
       fail "Timestamp of contents of archive file should be zero"
 }