Genrules only depend on the C++ toolchain if they have C++ make variables.

e.g.: cmd = "$(CC) foo.cc > $@"

Fixes #2729

--
PiperOrigin-RevId: 151369889
MOS_MIGRATED_REVID=151369889

8 files changed, 53 insertions, 30 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidBinaryRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidBinaryRule.java
index f39b2fa768..8fedd68833 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidBinaryRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/android/BazelAndroidBinaryRule.java
@@ -27,6 +27,7 @@ import com.google.devtools.build.lib.rules.android.AndroidBinaryOnlyRule;
 import com.google.devtools.build.lib.rules.android.AndroidConfiguration;
 import com.google.devtools.build.lib.rules.android.AndroidRuleClasses;
 import com.google.devtools.build.lib.rules.cpp.CppConfiguration;
+import com.google.devtools.build.lib.rules.cpp.CppRuleClasses;
 import com.google.devtools.build.lib.rules.java.JavaConfiguration;
 
 /**
@@ -45,7 +46,7 @@ public class BazelAndroidBinaryRule implements RuleDefinition {
             .value(environment.getToolsLabel("//tools/android:debug_keystore")))
         .add(attr(":cc_toolchain_split", BuildType.LABEL)
             .cfg(AndroidRuleClasses.ANDROID_SPLIT_TRANSITION)
-            .value(BazelCppRuleClasses.CC_TOOLCHAIN))
+            .value(CppRuleClasses.CC_TOOLCHAIN))
         /* <!-- #BLAZE_RULE(android_binary).IMPLICIT_OUTPUTS -->
          <ul>
          <li><code><var>name</var>.apk</code>: An Android application
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCcIncLibraryRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCcIncLibraryRule.java
index d4644ba3d5..071d5120a6 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCcIncLibraryRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCcIncLibraryRule.java
@@ -24,6 +24,7 @@ import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder;
 import com.google.devtools.build.lib.rules.cpp.CcIncLibraryRule;
 import com.google.devtools.build.lib.rules.cpp.CppConfiguration;
+import com.google.devtools.build.lib.rules.cpp.CppRuleClasses;
 
 /** Rule definition for the cc_inc_library class. */
 public final class BazelCcIncLibraryRule implements RuleDefinition {
@@ -31,7 +32,7 @@ public final class BazelCcIncLibraryRule implements RuleDefinition {
   public RuleClass build(Builder builder, RuleDefinitionEnvironment env) {
     return builder
         .requiresConfigurationFragments(CppConfiguration.class)
-        .add(attr(":cc_toolchain", LABEL).value(BazelCppRuleClasses.CC_TOOLCHAIN))
+        .add(attr(":cc_toolchain", LABEL).value(CppRuleClasses.CC_TOOLCHAIN))
         .add(attr(":stl", LABEL).value(BazelCppRuleClasses.STL))
         .build();
   }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCppRuleClasses.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCppRuleClasses.java
index 5889ab4c13..4374820738 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCppRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/BazelCppRuleClasses.java
@@ -107,28 +107,6 @@ public class BazelCppRuleClasses {
         }
       };
 
-  /**
-   * Label of a pseudo-filegroup that contains all crosstool and libcfiles for
-   * all configurations, as specified on the command-line.
-   */
-  public static final String CROSSTOOL_LABEL = "//tools/defaults:crosstool";
-
-  public static final LateBoundLabel<BuildConfiguration> DEFAULT_MALLOC =
-      new LateBoundLabel<BuildConfiguration>() {
-        @Override
-        public Label resolve(Rule rule, AttributeMap attributes, BuildConfiguration configuration) {
-          return configuration.getFragment(CppConfiguration.class).customMalloc();
-        }
-      };
-
-  public static final LateBoundLabel<BuildConfiguration> CC_TOOLCHAIN =
-      new LateBoundLabel<BuildConfiguration>(CROSSTOOL_LABEL, CppConfiguration.class) {
-        @Override
-        public Label resolve(Rule rule, AttributeMap attributes, BuildConfiguration configuration) {
-          return configuration.getFragment(CppConfiguration.class).getCcToolchainRuleLabel();
-        }
-      };
-
   public static final LateBoundLabel<BuildConfiguration> STL =
       new LateBoundLabel<BuildConfiguration>() {
         @Override
@@ -194,7 +172,7 @@ public class BazelCppRuleClasses {
     @SuppressWarnings("unchecked")
     public RuleClass build(Builder builder, RuleDefinitionEnvironment env) {
       return builder
-          .add(attr(":cc_toolchain", LABEL).value(CC_TOOLCHAIN))
+          .add(attr(":cc_toolchain", LABEL).value(CppRuleClasses.CC_TOOLCHAIN))
           .setPreferredDependencyPredicate(Predicates.<String>or(CPP_SOURCE, C_SOURCE, CPP_HEADER))
           .build();
     }
@@ -563,7 +541,7 @@ public class BazelCppRuleClasses {
                   .value(env.getToolsLabel("//tools/cpp:malloc"))
                   .allowedFileTypes()
                   .allowedRuleClasses("cc_library"))
-          .add(attr(":default_malloc", LABEL).value(DEFAULT_MALLOC))
+          .add(attr(":default_malloc", LABEL).value(CppRuleClasses.DEFAULT_MALLOC))
           /*<!-- #BLAZE_RULE($cc_binary_base).ATTRIBUTE(stamp) -->
           Enable link stamping.
           Whether to encode build information into the binary. Possible values:
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/proto/BazelCcProtoAspect.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/proto/BazelCcProtoAspect.java
index 023634e49d..9538ea0925 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/proto/BazelCcProtoAspect.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/cpp/proto/BazelCcProtoAspect.java
@@ -14,7 +14,7 @@
 
 package com.google.devtools.build.lib.bazel.rules.cpp.proto;
 
-import static com.google.devtools.build.lib.bazel.rules.cpp.BazelCppRuleClasses.CC_TOOLCHAIN;
+import static com.google.devtools.build.lib.rules.cpp.CppRuleClasses.CC_TOOLCHAIN;
 
 import com.google.devtools.build.lib.rules.cpp.CppSemantics;
 import com.google.devtools.build.lib.rules.cpp.proto.CcProtoAspect;
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
index fafd65d6a6..ccc2c6c042 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/genrule/BazelGenRuleRule.java
@@ -20,7 +20,6 @@ import static com.google.devtools.build.lib.syntax.Type.BOOLEAN;
 
 import com.google.devtools.build.lib.analysis.RuleDefinition;
 import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
-import com.google.devtools.build.lib.bazel.rules.cpp.BazelCppRuleClasses;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.rules.cpp.CppConfiguration;
 import com.google.devtools.build.lib.rules.genrule.GenRuleBaseRule;
@@ -52,7 +51,7 @@ public final class BazelGenRuleRule implements RuleDefinition {
         // TODO(bazel-team): stamping doesn't seem to work. Fix it or remove attribute.
         .add(attr("stamp", BOOLEAN).value(false))
 
-        .add(attr(":cc_toolchain", LABEL).value(BazelCppRuleClasses.CC_TOOLCHAIN))
+        .add(attr(":cc_toolchain", LABEL).value(GenRuleBaseRule.CC_TOOLCHAIN))
         .add(attr(":host_jdk", LABEL).cfg(HOST).value(JavaSemantics.HOST_JDK))
 
         .build();
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppRuleClasses.java
index 9ad6ba3fa1..698353a105 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppRuleClasses.java
@@ -87,6 +87,28 @@ public class CppRuleClasses {
     }
   }
 
+  /**
+   * Label of a pseudo-filegroup that contains all crosstool and libcfiles for all configurations,
+   * as specified on the command-line.
+   */
+  public static final String CROSSTOOL_LABEL = "//tools/defaults:crosstool";
+
+  public static final LateBoundLabel<BuildConfiguration> DEFAULT_MALLOC =
+      new LateBoundLabel<BuildConfiguration>() {
+        @Override
+        public Label resolve(Rule rule, AttributeMap attributes, BuildConfiguration configuration) {
+          return configuration.getFragment(CppConfiguration.class).customMalloc();
+        }
+      };
+
+  public static final LateBoundLabel<BuildConfiguration> CC_TOOLCHAIN =
+      new LateBoundLabel<BuildConfiguration>(CROSSTOOL_LABEL, CppConfiguration.class) {
+        @Override
+        public Label resolve(Rule rule, AttributeMap attributes, BuildConfiguration configuration) {
+          return configuration.getFragment(CppConfiguration.class).getCcToolchainRuleLabel();
+        }
+      };
+
   // Artifacts of these types are discarded from the 'hdrs' attribute in cc rules
   static final FileTypeSet DISALLOWED_HDRS_FILES = FileTypeSet.of(
       ARCHIVE,
diff --git a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBase.java b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBase.java
index a81a38ff1b..8a2983ba90 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBase.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBase.java
@@ -60,7 +60,7 @@ public abstract class GenRuleBase implements RuleConfiguredTargetFactory {
   private static final Pattern JDK_MAKE_VARIABLE =
       Pattern.compile("\\$\\((JAVABASE|JAVA)\\)");
 
-  protected boolean requiresCrosstool(String command) {
+  protected static boolean requiresCrosstool(String command) {
     return CROSSTOOL_MAKE_VARIABLE.matcher(command).find();
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBaseRule.java b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBaseRule.java
index 530f51b1ee..5bd7d09a7d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBaseRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleBaseRule.java
@@ -26,12 +26,18 @@ import com.google.devtools.build.lib.analysis.BaseRuleClasses;
 import com.google.devtools.build.lib.analysis.RuleDefinition;
 import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
 import com.google.devtools.build.lib.analysis.TransitiveInfoProvider;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.packages.Attribute;
 import com.google.devtools.build.lib.packages.AttributeMap;
 import com.google.devtools.build.lib.packages.BuildType;
+import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder.RuleClassType;
 import com.google.devtools.build.lib.rules.ToolchainProvider;
+import com.google.devtools.build.lib.rules.cpp.CppConfiguration;
+import com.google.devtools.build.lib.rules.cpp.CppRuleClasses;
+import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.util.FileTypeSet;
 
 /**
@@ -41,6 +47,22 @@ import com.google.devtools.build.lib.util.FileTypeSet;
  */
 public class GenRuleBaseRule implements RuleDefinition {
 
+  /**
+   * Late-bound dependency on the C++ toolchain <i>iff</i> the genrule has make variables that need
+   * that toolchain.
+   */
+  public static final Attribute.LateBoundLabel<BuildConfiguration> CC_TOOLCHAIN =
+      new Attribute.LateBoundLabel<BuildConfiguration>(
+          CppRuleClasses.CROSSTOOL_LABEL, CppConfiguration.class) {
+        @Override
+        public Label resolve(Rule rule, AttributeMap attributes, BuildConfiguration configuration) {
+          return attributes != null
+              && GenRuleBase.requiresCrosstool(attributes.get("cmd", Type.STRING))
+              ? CppRuleClasses.CC_TOOLCHAIN.resolve(rule, attributes, configuration)
+              : null;
+        }
+      };
+
   @Override
   public RuleClass build(
       RuleClass.Builder builder, RuleDefinitionEnvironment env) {