valgrind error in tsvectorin

Was just running the regression tests under valgrind and aside from the usual
false positives caused by structure padding I noticed this:

==19366== Source and destination overlap in memcpy(0x4BB7FC0, 0x4BB7FC0, 12)
==19366==    at 0x4026B12: memcpy (mc_replace_strmem.c:402)
==19366==    by 0x8389750: uniqueentry (tsvector.c:128)
==19366==    by 0x8389C63: tsvectorin (tsvector.c:265)
==19366==    by 0x83B1888: InputFunctionCall (fmgr.c:1878)
==19366==    by 0x83B1B46: OidInputFunctionCall (fmgr.c:2009)
==19366==    by 0x8171651: stringTypeDatum (parse_type.c:497)
==19366==    by 0x8171CAC: coerce_type (parse_coerce.c:239)
==19366==    by 0x8171A72: coerce_to_target_type (parse_coerce.c:86)
==19366==    by 0x8166DB5: transformTypeCast (parse_expr.c:2016)
==19366==    by 0x8162FA8: transformExpr (parse_expr.c:181)
==19366==    by 0x8174990: transformTargetEntry (parse_target.c:75)
==19366==    by 0x8174B01: transformTargetList (parse_target.c:145)

After a quick glance at the code I suspect res and ptr end up pointing to the
same object, perhaps the loop condition has a fencepost error. But I don't
really understand what it's trying to do at all.

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's PostGIS support!