2 files changed, 70 insertions, 0 deletions

diff --git a/src/backend/access/gist/gist.c b/src/backend/access/gist/gist.c
index 79fe6eb8d62..25b42e38f22 100644
--- a/src/backend/access/gist/gist.c
+++ b/src/backend/access/gist/gist.c
@@ -92,6 +92,7 @@ gisthandler(PG_FUNCTION_ARGS)
 	amroutine->amproperty = gistproperty;
 	amroutine->ambuildphasename = NULL;
 	amroutine->amvalidate = gistvalidate;
+	amroutine->amadjustmembers = gistadjustmembers;
 	amroutine->ambeginscan = gistbeginscan;
 	amroutine->amrescan = gistrescan;
 	amroutine->amgettuple = gistgettuple;
diff --git a/src/backend/access/gist/gistvalidate.c b/src/backend/access/gist/gistvalidate.c
index a285736a810..2b9ab693be1 100644
--- a/src/backend/access/gist/gistvalidate.c
+++ b/src/backend/access/gist/gistvalidate.c
@@ -279,3 +279,72 @@ gistvalidate(Oid opclassoid)
 
 	return result;
 }
+
+/*
+ * Prechecking function for adding operators/functions to a GiST opfamily.
+ */
+void
+gistadjustmembers(Oid opfamilyoid,
+				  Oid opclassoid,
+				  List *operators,
+				  List *functions)
+{
+	ListCell   *lc;
+
+	/*
+	 * Operator members of a GiST opfamily should never have hard
+	 * dependencies, since their connection to the opfamily depends only on
+	 * what the support functions think, and that can be altered.  For
+	 * consistency, we make all soft dependencies point to the opfamily,
+	 * though a soft dependency on the opclass would work as well in the
+	 * CREATE OPERATOR CLASS case.
+	 */
+	foreach(lc, operators)
+	{
+		OpFamilyMember *op = (OpFamilyMember *) lfirst(lc);
+
+		op->ref_is_hard = false;
+		op->ref_is_family = true;
+		op->refobjid = opfamilyoid;
+	}
+
+	/*
+	 * Required support functions should have hard dependencies.  Preferably
+	 * those are just dependencies on the opclass, but if we're in ALTER
+	 * OPERATOR FAMILY, we leave the dependency pointing at the whole
+	 * opfamily.  (Given that GiST opclasses generally don't share opfamilies,
+	 * it seems unlikely to be worth working harder.)
+	 */
+	foreach(lc, functions)
+	{
+		OpFamilyMember *op = (OpFamilyMember *) lfirst(lc);
+
+		switch (op->number)
+		{
+			case GIST_CONSISTENT_PROC:
+			case GIST_UNION_PROC:
+			case GIST_PENALTY_PROC:
+			case GIST_PICKSPLIT_PROC:
+			case GIST_EQUAL_PROC:
+				/* Required support function */
+				op->ref_is_hard = true;
+				break;
+			case GIST_COMPRESS_PROC:
+			case GIST_DECOMPRESS_PROC:
+			case GIST_DISTANCE_PROC:
+			case GIST_FETCH_PROC:
+			case GIST_OPTIONS_PROC:
+				/* Optional, so force it to be a soft family dependency */
+				op->ref_is_hard = false;
+				op->ref_is_family = true;
+				op->refobjid = opfamilyoid;
+				break;
+			default:
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+						 errmsg("support function number %d is invalid for access method %s",
+								op->number, "gist")));
+				break;
+		}
+	}
+}