From: Peter Eisentraut <peter@eisentraut.org>
Date: Fri, 8 Aug 2025 10:06:06 +0000 (+0200)
Subject: Fix incorrect lack of Datum conversion in _int_matchsel()
X-Git-Tag: REL_16_10~8
X-Git-Url: http://waps.l3s.uni-hannover.de/gitweb/?a=commitdiff_plain;h=a3906b44c5b920cd7beb569a097660f487adf883;p=postgresql.git

Fix incorrect lack of Datum conversion in _int_matchsel()

The code used

    return (Selectivity) 0.0;

where

    PG_RETURN_FLOAT8(0.0);

would be correct.

On 64-bit systems, these are pretty much equivalent, but on 32-bit
systems, PG_RETURN_FLOAT8() correctly produces a pointer, but the old
wrong code would return a null pointer, possibly leading to a crash
elsewhere.

We think this code is actually not reachable because bqarr_in won't
accept an empty query, and there is no other function that will
create query_int values.  But better be safe and not let such
incorrect code lie around.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/8246d7ff-f4b7-4363-913e-827dadfeb145%40eisentraut.org
---

diff --git a/contrib/intarray/_int_selfuncs.c b/contrib/intarray/_int_selfuncs.c
index 01d6fe14a70..17dc6768ea5 100644
--- a/contrib/intarray/_int_selfuncs.c
+++ b/contrib/intarray/_int_selfuncs.c
@@ -178,7 +178,7 @@ _int_matchsel(PG_FUNCTION_ARGS)
 	if (query->size == 0)
 	{
 		ReleaseVariableStats(vardata);
-		return (Selectivity) 0.0;
+		PG_RETURN_FLOAT8(0.0);
 	}
 
 	/*