예제 #1
0
    /**
     * Creates a middleman for the compilation prerequisites.
     *
     * @return the middleman or null if there are no prerequisites
     */
    private Artifact createMiddleman(ActionOwner owner, MiddlemanFactory middlemanFactory) {
      if (compilationPrerequisites.isEmpty()) {
        return null;
      }

      // Compilation prerequisites gathered in the compilationPrerequisites
      // must be generated prior to executing C++ compilation step that depends
      // on them (since these prerequisites include all potential header files, etc
      // that could be referenced during compilation). So there is a definite need
      // to ensure scheduling edge dependency. However, those prerequisites should
      // have no effect on the decision whether C++ compilation should happen in
      // the first place - only CppCompileAction outputs (*.o and *.d files) and
      // all files referenced by the *.d file should be used to make that decision.
      // If this action was never executed, then *.d file would be missing, forcing
      // compilation to occur. If *.d file is present and has not changed then the
      // only reason that would force us to re-compile would be change in one of
      // the files referenced by the *.d file, since no other files participated
      // in the compilation. We also need to propagate errors through this
      // dependency link. So we use an error propagating middleman.
      // Such middleman will be ignored by the dependency checker yet will still
      // represent an edge in the action dependency graph - forcing proper execution
      // order and error propagation.
      return middlemanFactory.createErrorPropagatingMiddleman(
          owner,
          ruleContext.getLabel().toString(),
          purpose,
          ImmutableList.copyOf(compilationPrerequisites),
          ruleContext
              .getConfiguration()
              .getMiddlemanDirectory(ruleContext.getRule().getRepository()));
    }
예제 #2
0
    /**
     * Returns the same set of artifacts as createMiddleman() would, but without actually creating
     * middlemen.
     */
    private Artifact getMiddlemanArtifact(MiddlemanFactory middlemanFactory) {
      if (compilationPrerequisites.isEmpty()) {
        return null;
      }

      return middlemanFactory.getErrorPropagatingMiddlemanArtifact(
          ruleContext.getLabel().toString(),
          purpose,
          ruleContext
              .getConfiguration()
              .getMiddlemanDirectory(ruleContext.getRule().getRepository()));
    }