http://tip.golang.org/pkg/runtime/race/
contains:
"
Command race

Package race provides low-level facilities for data race detection.

This program is used to verify the race detector by running the tests and parsing their
output. It does not check stack correctness, completeness or anything else: it merely
verifies that if a test is expected to be racy then the race is detected.
"

This is package rather than a command, and the comment for the test driver should not be
visible here.