postgrespro
diff --git a/‎src/backend/access/gist/gist.c
Lines changed: 10 additions & 0 deletions b/‎src/backend/access/gist/gist.c
Lines changed: 10 additions & 0 deletions
@@ -1030,6 +1030,9 @@ gistnewroot(Relation r, Buffer buffer, IndexTuple *itup, int len, ItemPointer ke
 	END_CRIT_SECTION();
 }
 
+/*
+ * Fill a GISTSTATE with information about the index
+ */
 void
 initGISTstate(GISTSTATE *giststate, Relation index)
 {
@@ -1064,6 +1067,13 @@ initGISTstate(GISTSTATE *giststate, Relation index)
 		fmgr_info_copy(&(giststate->equalFn[i]),
 					   index_getprocinfo(index, i + 1, GIST_EQUAL_PROC),
 					   CurrentMemoryContext);
+		/* opclasses are not required to provide a Distance method */
+		if (OidIsValid(index_getprocid(index, i + 1, GIST_DISTANCE_PROC)))
+			fmgr_info_copy(&(giststate->distanceFn[i]),
+						   index_getprocinfo(index, i + 1, GIST_DISTANCE_PROC),
+						   CurrentMemoryContext);
+		else
+			giststate->distanceFn[i].fn_oid = InvalidOid;
 	}
 }
Original file line number	Diff line number	Diff line change
`@@ -1030,6 +1030,9 @@ gistnewroot(Relation r, Buffer buffer, IndexTuple *itup, int len, ItemPointer ke`
`1030`	`1030`	`END_CRIT_SECTION();`
`1031`	`1031`	`}`
`1032`	`1032`
	`1033`	`+/*`
	`1034`	`+ * Fill a GISTSTATE with information about the index`
	`1035`	`+ */`
`1033`	`1036`	`void`
`1034`	`1037`	`initGISTstate(GISTSTATE *giststate, Relation index)`
`1035`	`1038`	`{`
`@@ -1064,6 +1067,13 @@ initGISTstate(GISTSTATE *giststate, Relation index)`
`1064`	`1067`	`fmgr_info_copy(&(giststate->equalFn[i]),`
`1065`	`1068`	`index_getprocinfo(index, i + 1, GIST_EQUAL_PROC),`
`1066`	`1069`	`CurrentMemoryContext);`
	`1070`	`+ /* opclasses are not required to provide a Distance method */`
	`1071`	`+ if (OidIsValid(index_getprocid(index, i + 1, GIST_DISTANCE_PROC)))`
	`1072`	`+ fmgr_info_copy(&(giststate->distanceFn[i]),`
	`1073`	`+ index_getprocinfo(index, i + 1, GIST_DISTANCE_PROC),`
	`1074`	`+ CurrentMemoryContext);`
	`1075`	`+ else`
	`1076`	`+ giststate->distanceFn[i].fn_oid = InvalidOid;`
`1067`	`1077`	`}`
`1068`	`1078`	`}`
`1069`	`1079`