Implement objc++ linking semantics in crosstool. Sematics in question are:

1) Uses clang++ instead of clang.
2) Add -stdlib=libc++ and -std=gnu++11 linker args

--
MOS_MIGRATED_REVID=140049151

3 files changed, 20 insertions, 6 deletions

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 74f33ab913..bddde77baf 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
@@ -16,7 +16,6 @@ package com.google.devtools.build.lib.rules.cpp;
 
 import com.google.common.collect.AbstractIterator;
 import com.google.common.collect.ImmutableList;
-import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.collect.CollectionUtils;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.rules.cpp.LinkerInputs.LibraryToLink;
@@ -152,7 +151,16 @@ public abstract class Link {
         Picness.NOPIC,
         ArtifactCategory.EXECUTABLE,
         Executable.EXECUTABLE),
-    
+
+    /** An objc executable that includes objc++/c++ source. */
+    OBJCPP_EXECUTABLE(
+        "",
+        Staticness.STATIC,
+        "objc++-executable",
+        Picness.NOPIC,
+        ArtifactCategory.EXECUTABLE,
+        Executable.EXECUTABLE),
+
     /** A static archive with .pic.o object files (compiled with -fPIC). */
     PIC_STATIC_LIBRARY(
         ".pic.a",
@@ -357,8 +365,6 @@ public abstract class Link {
 
       while (inputs.hasNext()) {
         LibraryToLink inputLibrary = inputs.next();
-        Artifact input = inputLibrary.getArtifact();
-        String name = input.getFilename();
 
         // True if the linker might use the members of this file, i.e., if the file is a thin or
         // start_end_lib archive (aka static library). Also check if the library contains object
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 6a95202423..5522fe5d26 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
@@ -409,6 +409,7 @@ public final class LinkCommandLine extends CommandLine {
       case OBJC_ARCHIVE:
       case OBJC_FULLY_LINKED_ARCHIVE:
       case OBJC_EXECUTABLE:
+      case OBJCPP_EXECUTABLE:
         argv.add(toolPath);
         argv.addAll(featureConfiguration.getCommandLine(actionName, variables));
         break;
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/CrosstoolCompilationSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/CrosstoolCompilationSupport.java
index 21d7cd3849..ada735b27d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/CrosstoolCompilationSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/CrosstoolCompilationSupport.java
@@ -44,6 +44,7 @@ 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.ObjcProvider.Flag;
 import com.google.devtools.build.lib.rules.objc.ObjcVariablesExtension.VariableCategory;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import java.util.Collection;
@@ -67,6 +68,7 @@ public class CrosstoolCompilationSupport extends CompilationSupport {
           "objc-archive",
           "objc-fully-link",
           "objc-executable",
+          "objc++-executable",
           "assemble",
           "preprocess-assemble",
           "c-compile",
@@ -188,6 +190,10 @@ public class CrosstoolCompilationSupport extends CompilationSupport {
 
     registerObjFilelistAction(objFiles, inputFileList);
 
+    LinkTargetType linkType = (objcProvider.is(Flag.USES_CPP))
+        ? LinkTargetType.OBJCPP_EXECUTABLE
+        : LinkTargetType.OBJC_EXECUTABLE;
+    
     ObjcVariablesExtension extension = new ObjcVariablesExtension.Builder()
         .setRuleContext(ruleContext)
         .setObjcProvider(objcProvider)
@@ -199,7 +205,7 @@ public class CrosstoolCompilationSupport extends CompilationSupport {
         .setAttributeLinkopts(attributes.linkopts())
         .addVariableCategory(VariableCategory.EXECUTABLE_LINKING_VARIABLES)
         .build();
-    
+   
     Artifact binaryToLink = getBinaryToLink();
     CppLinkAction executableLinkAction =
         new CppLinkActionBuilder(ruleContext, binaryToLink)
@@ -209,9 +215,10 @@ public class CrosstoolCompilationSupport extends CompilationSupport {
             .addTransitiveActionInputs(objcProvider.get(IMPORTED_LIBRARY))
             .addTransitiveActionInputs(objcProvider.get(STATIC_FRAMEWORK_FILE))
             .addTransitiveActionInputs(objcProvider.get(DYNAMIC_FRAMEWORK_FILE))
+            .setCrosstoolInputs(CppHelper.getToolchain(ruleContext).getLink())
             .addActionInputs(prunedJ2ObjcArchives)
             .addActionInput(inputFileList)
-            .setLinkType(LinkTargetType.OBJC_EXECUTABLE)
+            .setLinkType(linkType)
             .setLinkStaticness(LinkStaticness.FULLY_STATIC)
             .addVariablesExtension(extension)
             .setFeatureConfiguration(getFeatureConfiguration(ruleContext))