diff --git a/src/backend/utils/adt/array_userfuncs.c b/src/backend/utils/adt/array_userfuncs.c
index c0abc3fb3e..bfcccea46a 100644
--- a/src/backend/utils/adt/array_userfuncs.c
+++ b/src/backend/utils/adt/array_userfuncs.c
@@ -651,7 +651,6 @@ array_position_common(FunctionCallInfo fcinfo)
 		PG_RETURN_NULL();
 
 	array = PG_GETARG_ARRAYTYPE_P(0);
-	element_type = ARR_ELEMTYPE(array);
 
 	/*
 	 * We refuse to search for elements in multi-dimensional arrays, since we
@@ -662,6 +661,10 @@ array_position_common(FunctionCallInfo fcinfo)
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("searching for elements in multidimensional arrays is not supported")));
 
+	/* Searching in an empty array is well-defined, though: it always fails */
+	if (ARR_NDIM(array) < 1)
+		PG_RETURN_NULL();
+
 	if (PG_ARGISNULL(1))
 	{
 		/* fast return when the array doesn't have nulls */
@@ -676,6 +679,7 @@ array_position_common(FunctionCallInfo fcinfo)
 		null_search = false;
 	}
 
+	element_type = ARR_ELEMTYPE(array);
 	position = (ARR_LBOUND(array))[0] - 1;
 
 	/* figure out where to start */
@@ -801,9 +805,6 @@ array_positions(PG_FUNCTION_ARGS)
 		PG_RETURN_NULL();
 
 	array = PG_GETARG_ARRAYTYPE_P(0);
-	element_type = ARR_ELEMTYPE(array);
-
-	position = (ARR_LBOUND(array))[0] - 1;
 
 	/*
 	 * We refuse to search for elements in multi-dimensional arrays, since we
@@ -816,6 +817,10 @@ array_positions(PG_FUNCTION_ARGS)
 
 	astate = initArrayResult(INT4OID, CurrentMemoryContext, false);
 
+	/* Searching in an empty array is well-defined, though: it always fails */
+	if (ARR_NDIM(array) < 1)
+		PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext));
+
 	if (PG_ARGISNULL(1))
 	{
 		/* fast return when the array doesn't have nulls */
@@ -830,6 +835,9 @@ array_positions(PG_FUNCTION_ARGS)
 		null_search = false;
 	}
 
+	element_type = ARR_ELEMTYPE(array);
+	position = (ARR_LBOUND(array))[0] - 1;
+
 	/*
 	 * We arrange to look up type info for array_create_iterator only once per
 	 * series of calls, assuming the element type doesn't change underneath