The constant kTraceBufferLen is only referenced in code guarded by the macro define TRACE_ENABLED. And trunk clang identifies that this constant is unused otherwise. We should only define this constant when building with TRACE_ENABLED.
Created attachment 218303 [details] Patch
Filed ANGLE bug for this issue: <https://code.google.com/p/angleproject/issues/detail?id=534>.
Committed r160018: <http://trac.webkit.org/changeset/160018>