Thread: CVS HEAD dumps core on simple tsvector input example
regression=# SELECT 'a very fat cat sat:4 on:5 a:6 mat:7'::tsvector; tsvector -----------------------------------------------'a' 'on':5 'cat' 'fat' 'mat':7 'sat':4 'very' (1 row) regression=# SELECT 'a very fat cat sat:4 on:5 a:6 mat:7'::tsvector; server closed the connection unexpectedly Notice it's the same input both times --- only the second one crashes. The coredump happens inside repalloc, making me suspect a memory clobber is involved. BTW, why does the 'a':6 lexeme disappear? To the extent that I understand how this should work, I'd have expected 'a' and 'a':6 to merge into 'a':6 not plain 'a'. regards, tom lane
Tom Lane wrote: > BTW, why does the 'a':6 lexeme disappear? To the extent that I > understand how this should work, I'd have expected 'a' and 'a':6 > to merge into 'a':6 not plain 'a'. 'a':1,6 perhaps? -- Alvaro Herrera http://www.amazon.com/gp/registry/DXLWNGRJD34J We take risks not to escape from life, but to prevent life escaping from us.
Alvaro Herrera <alvherre@commandprompt.com> writes: > Tom Lane wrote: >> BTW, why does the 'a':6 lexeme disappear? To the extent that I >> understand how this should work, I'd have expected 'a' and 'a':6 >> to merge into 'a':6 not plain 'a'. > 'a':1,6 perhaps? No, it would be inappropriate to add a '1' that wasn't specified. My reasoning is that 'a':1 and 'a':6 are distinct bits of information, hence their combination is 'a':1,6. But 'a' doesn't give any more information than 'a':6 so it should be dropped by the duplicate-elimination code. It's not clear to me whether that's what Oleg and Teodor think, though. Hm, just found a variant of the bug: regression=# select 'a a:6'::tsvector;tsvector ----------'a' (1 row) regression=# select 'a a:6'::tsvector; tsvector --------------------------------------------------------------------------'a':6,16255C,0,12C,8C,2640,0,512,0,312,12C,400C,0,312,0,1,0,0,8448C,21,6 (1 row) This makes it look even more like a memory-corruption issue. regards, tom lane