Please check the FAQ; if you cannot find the answer there, please raise the issue in the Intel Cilk Plus Forum.
The source code submitted to the GCC “cilkplus” branch includes unit tests. The unit tests accomplish basic performance testing of the various small constructs in Intel Cilk Plus. There are also examples that time themselves for doing basic performance measurements. This is an area that we think can use additional attention.
Before submitting a bug, please search the Intel Cilk Plus Forum for similar issues. Please check Intel Cilk Plus FAQ before you submit it.