Re: valgrind error in tsvectorin

Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> 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.

Yeah, it looks like the memcpy is sometimes unnecessary because res and
ptr point to the same place. It might be worth cleaning up just to
avoid the valgrind warning, but I doubt it would save any noticeable
number of cycles.

regards, tom lane