diff --git a/contrib/intarray/_int_bool.c b/contrib/intarray/_int_bool.c
index 4382f882939..abac3ced433 100644
--- a/contrib/intarray/_int_bool.c
+++ b/contrib/intarray/_int_bool.c
@@ -90,12 +90,13 @@ gettoken(WORKSTATE *state, int32 *val)
 				else
 				{
 					long		lval;
+					char	   *endptr;
 
 					nnn[innn] = '\0';
 					errno = 0;
-					lval = strtol(nnn, NULL, 0);
+					lval = strtol(nnn, &endptr, 10);
 					*val = (int32) lval;
-					if (errno != 0 || (long) *val != lval)
+					if (errno != 0 || *endptr != '\0' || (long) *val != lval)
 						return ERR;
 					state->state = WAITOPERATOR;
 					return (state->count && *(state->buf) == '\0')
diff --git a/contrib/intarray/expected/_int.out b/contrib/intarray/expected/_int.out
index fb4086a95ca..4a2ecba8081 100644
--- a/contrib/intarray/expected/_int.out
+++ b/contrib/intarray/expected/_int.out
@@ -398,6 +398,16 @@ SELECT '1&(2&(4&(5|!6)))'::query_int;
  1 & 2 & 4 & ( 5 | !6 )
 (1 row)
 
+SELECT '010'::query_int;  -- decimal, not octal
+ query_int 
+-----------
+ 10
+(1 row)
+
+SELECT '-'::query_int;  -- syntax error
+ERROR:  syntax error
+LINE 1: SELECT '-'::query_int;
+               ^
 -- Test for overflow of the int16 "left" field in findoprnd().
 -- This query uses a balanced binary tree to avoid using too much stack.
 DO $$
diff --git a/contrib/intarray/sql/_int.sql b/contrib/intarray/sql/_int.sql
index 0d30914725e..7a1d07e15d1 100644
--- a/contrib/intarray/sql/_int.sql
+++ b/contrib/intarray/sql/_int.sql
@@ -74,6 +74,8 @@ SELECT '1&(2&(4&(5&6)))'::query_int;
 SELECT '1&2&4&5&6'::query_int;
 SELECT '1&(2&(4&(5|6)))'::query_int;
 SELECT '1&(2&(4&(5|!6)))'::query_int;
+SELECT '010'::query_int;  -- decimal, not octal
+SELECT '-'::query_int;  -- syntax error
 
 -- Test for overflow of the int16 "left" field in findoprnd().
 -- This query uses a balanced binary tree to avoid using too much stack.