Add ThinLTO support for py_binary targets.

Builds of py_binary targets were failing with --features=thin_lto
during the link because the C++ source files were compiled into
bitcode, but the link (which is set up by GooglePythonSemantics.java) did
not have support for ThinLTO actions and attempted to do a native link of
the bitcode objects.

--
PiperOrigin-RevId: 150201765
MOS_MIGRATED_REVID=150201765

1 files changed, 7 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkAction.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkAction.java
index 26011cbcf5..6a389250a1 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppLinkAction.java
@@ -571,6 +571,7 @@ public final class CppLinkAction extends AbstractAction
     final ImmutableSet<Artifact> nonCodeInputs;
     final NestedSet<LibraryToLink> libraries;
     final NestedSet<Artifact> crosstoolInputs;
+    final ImmutableList<Artifact> ltoBitcodeFiles;
     final Artifact runtimeMiddleman;
     final NestedSet<Artifact> runtimeInputs;
     final ArtifactCategory runtimeType;
@@ -596,6 +597,7 @@ public final class CppLinkAction extends AbstractAction
           .addTransitive(builder.getLibraries().build()).build();
       this.crosstoolInputs =
           NestedSetBuilder.<Artifact>stableOrder().addTransitive(builder.getCrosstoolInputs()).build();
+      this.ltoBitcodeFiles = ImmutableList.copyOf(builder.getLtoBitcodeFiles());
       this.runtimeMiddleman = builder.getRuntimeMiddleman();
       this.runtimeInputs =
           NestedSetBuilder.<Artifact>stableOrder().addTransitive(builder.getRuntimeInputs()).build();
@@ -632,6 +634,11 @@ public final class CppLinkAction extends AbstractAction
       return this.crosstoolInputs;
     }
     
+    /** Returns linker inputs that are lto bitcode files. */
+    public ImmutableList<Artifact> getLtoBitcodeFiles() {
+      return this.ltoBitcodeFiles;
+    }
+    
     /**
      * Returns the runtime middleman artifact.
      */