Mark built-in btree comparison functions as leakproof where it's safe.

Generally, if the comparison operators for a datatype or pair of datatypes
are leakproof, the corresponding btree comparison support function can be
considered so as well.  But we had not originally worried about marking
support functions as leakproof, reasoning that they'd not likely be used in
queries so the marking wouldn't matter.  It turns out there's at least one
place where it does matter: calc_arraycontsel() finds the target datatype's
default btree comparison function and tries to use that to estimate
selectivity, but it will be blocked in some cases if the function isn't
leakproof.  This leads to unnecessarily poor selectivity estimates and bad
plans, as seen in bug #15251.

Hence, run around and apply proleakproof markings where the corresponding
btree comparison operators are leakproof.  (I did eyeball each function
to verify that it wasn't doing anything surprising, too.)

This isn't a full solution to bug #15251, and it's not back-patchable
because of the need for a catversion bump.  A more useful response probably
is to consider whether we can check permissions on the parent table instead
of the child.  However, this change will help in some cases where that
won't, and it's easy enough to do in HEAD, so let's do so.

Discussion: https://postgr.es/m/3876.1531261875@sss.pgh.pa.us

Author: tglsfdc

src/include/catalog/catversion.h

@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	201806231
+#define CATALOG_VERSION_NO	201807111
 
 #endif

src/include/catalog/pg_proc.dat

@@ -1004,53 +1004,53 @@
   prosrc => 'poly_out' },
 
 { oid => '350', descr => 'less-equal-greater',
-  proname => 'btint2cmp', prorettype => 'int4', proargtypes => 'int2 int2',
-  prosrc => 'btint2cmp' },
+  proname => 'btint2cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int2 int2', prosrc => 'btint2cmp' },
 { oid => '3129', descr => 'sort support',
   proname => 'btint2sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btint2sortsupport' },
 { oid => '351', descr => 'less-equal-greater',
-  proname => 'btint4cmp', prorettype => 'int4', proargtypes => 'int4 int4',
-  prosrc => 'btint4cmp' },
+  proname => 'btint4cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int4 int4', prosrc => 'btint4cmp' },
 { oid => '3130', descr => 'sort support',
   proname => 'btint4sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btint4sortsupport' },
 { oid => '842', descr => 'less-equal-greater',
-  proname => 'btint8cmp', prorettype => 'int4', proargtypes => 'int8 int8',
-  prosrc => 'btint8cmp' },
+  proname => 'btint8cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int8 int8', prosrc => 'btint8cmp' },
 { oid => '3131', descr => 'sort support',
   proname => 'btint8sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btint8sortsupport' },
 { oid => '354', descr => 'less-equal-greater',
-  proname => 'btfloat4cmp', prorettype => 'int4',
+  proname => 'btfloat4cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'float4 float4', prosrc => 'btfloat4cmp' },
 { oid => '3132', descr => 'sort support',
   proname => 'btfloat4sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btfloat4sortsupport' },
 { oid => '355', descr => 'less-equal-greater',
-  proname => 'btfloat8cmp', prorettype => 'int4',
+  proname => 'btfloat8cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'float8 float8', prosrc => 'btfloat8cmp' },
 { oid => '3133', descr => 'sort support',
   proname => 'btfloat8sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btfloat8sortsupport' },
 { oid => '356', descr => 'less-equal-greater',
-  proname => 'btoidcmp', prorettype => 'int4', proargtypes => 'oid oid',
-  prosrc => 'btoidcmp' },
+  proname => 'btoidcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'oid oid', prosrc => 'btoidcmp' },
 { oid => '3134', descr => 'sort support',
   proname => 'btoidsortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btoidsortsupport' },
 { oid => '404', descr => 'less-equal-greater',
   proname => 'btoidvectorcmp', prorettype => 'int4',
   proargtypes => 'oidvector oidvector', prosrc => 'btoidvectorcmp' },
 { oid => '357', descr => 'less-equal-greater',
-  proname => 'btabstimecmp', prorettype => 'int4',
+  proname => 'btabstimecmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'abstime abstime', prosrc => 'btabstimecmp' },
 { oid => '358', descr => 'less-equal-greater',
-  proname => 'btcharcmp', prorettype => 'int4', proargtypes => 'char char',
-  prosrc => 'btcharcmp' },
+  proname => 'btcharcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'char char', prosrc => 'btcharcmp' },
 { oid => '359', descr => 'less-equal-greater',
-  proname => 'btnamecmp', prorettype => 'int4', proargtypes => 'name name',
-  prosrc => 'btnamecmp' },
+  proname => 'btnamecmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'name name', prosrc => 'btnamecmp' },
 { oid => '3135', descr => 'sort support',
   proname => 'btnamesortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'btnamesortsupport' },
@@ -1061,13 +1061,13 @@
   proname => 'bttextsortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'bttextsortsupport' },
 { oid => '377', descr => 'less-equal-greater',
-  proname => 'cash_cmp', prorettype => 'int4', proargtypes => 'money money',
-  prosrc => 'cash_cmp' },
+  proname => 'cash_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'money money', prosrc => 'cash_cmp' },
 { oid => '380', descr => 'less-equal-greater',
-  proname => 'btreltimecmp', prorettype => 'int4',
+  proname => 'btreltimecmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'reltime reltime', prosrc => 'btreltimecmp' },
 { oid => '381', descr => 'less-equal-greater',
-  proname => 'bttintervalcmp', prorettype => 'int4',
+  proname => 'bttintervalcmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'tinterval tinterval', prosrc => 'bttintervalcmp' },
 { oid => '382', descr => 'less-equal-greater',
   proname => 'btarraycmp', prorettype => 'int4',
@@ -2172,8 +2172,8 @@
   proname => 'date_ne', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'date date', prosrc => 'date_ne' },
 { oid => '1092', descr => 'less-equal-greater',
-  proname => 'date_cmp', prorettype => 'int4', proargtypes => 'date date',
-  prosrc => 'date_cmp' },
+  proname => 'date_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'date date', prosrc => 'date_cmp' },
 { oid => '3136', descr => 'sort support',
   proname => 'date_sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'date_sortsupport' },
@@ -2200,8 +2200,8 @@
   proname => 'time_ne', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'time time', prosrc => 'time_ne' },
 { oid => '1107', descr => 'less-equal-greater',
-  proname => 'time_cmp', prorettype => 'int4', proargtypes => 'time time',
-  prosrc => 'time_cmp' },
+  proname => 'time_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'time time', prosrc => 'time_cmp' },
 { oid => '1138', descr => 'larger of two',
   proname => 'date_larger', prorettype => 'date', proargtypes => 'date date',
   prosrc => 'date_larger' },
@@ -2576,8 +2576,8 @@
   proname => 'tidle', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'tid tid', prosrc => 'tidle' },
 { oid => '2794', descr => 'less-equal-greater',
-  proname => 'bttidcmp', prorettype => 'int4', proargtypes => 'tid tid',
-  prosrc => 'bttidcmp' },
+  proname => 'bttidcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'tid tid', prosrc => 'bttidcmp' },
 { oid => '2795', descr => 'larger of two',
   proname => 'tidlarger', prorettype => 'tid', proargtypes => 'tid tid',
   prosrc => 'tidlarger' },
@@ -2678,10 +2678,10 @@
   proname => 'timestamptypmodout', prorettype => 'cstring',
   proargtypes => 'int4', prosrc => 'timestamptypmodout' },
 { oid => '1314', descr => 'less-equal-greater',
-  proname => 'timestamptz_cmp', prorettype => 'int4',
+  proname => 'timestamptz_cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'timestamptz timestamptz', prosrc => 'timestamp_cmp' },
 { oid => '1315', descr => 'less-equal-greater',
-  proname => 'interval_cmp', prorettype => 'int4',
+  proname => 'interval_cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'interval interval', prosrc => 'interval_cmp' },
 { oid => '1316', descr => 'convert timestamp to time',
   proname => 'time', prorettype => 'time', proargtypes => 'timestamp',
@@ -2778,8 +2778,8 @@
   proname => 'timetz_gt', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'timetz timetz', prosrc => 'timetz_gt' },
 { oid => '1358', descr => 'less-equal-greater',
-  proname => 'timetz_cmp', prorettype => 'int4', proargtypes => 'timetz timetz',
-  prosrc => 'timetz_cmp' },
+  proname => 'timetz_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'timetz timetz', prosrc => 'timetz_cmp' },
 { oid => '1359',
   descr => 'convert date and time with time zone to timestamp with time zone',
   proname => 'timestamptz', prorettype => 'timestamptz',
@@ -3317,8 +3317,8 @@
   proname => 'bitlt', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'bit bit', prosrc => 'bitlt' },
 { oid => '1596', descr => 'less-equal-greater',
-  proname => 'bitcmp', prorettype => 'int4', proargtypes => 'bit bit',
-  prosrc => 'bitcmp' },
+  proname => 'bitcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'bit bit', prosrc => 'bitcmp' },
 
 { oid => '1598', descr => 'random value',
   proname => 'random', provolatile => 'v', proparallel => 'r',
@@ -3774,8 +3774,8 @@
   proname => 'varbitlt', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'varbit varbit', prosrc => 'bitlt' },
 { oid => '1672', descr => 'less-equal-greater',
-  proname => 'varbitcmp', prorettype => 'int4', proargtypes => 'varbit varbit',
-  prosrc => 'bitcmp' },
+  proname => 'varbitcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'varbit varbit', prosrc => 'bitcmp' },
 
 # avoid the C names bitand and bitor, since they are C++ keywords
 { oid => '1673',
@@ -3877,7 +3877,7 @@
   proname => 'macaddr_ne', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'macaddr macaddr', prosrc => 'macaddr_ne' },
 { oid => '836', descr => 'less-equal-greater',
-  proname => 'macaddr_cmp', prorettype => 'int4',
+  proname => 'macaddr_cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'macaddr macaddr', prosrc => 'macaddr_cmp' },
 { oid => '3144',
   proname => 'macaddr_not', prorettype => 'macaddr', proargtypes => 'macaddr',
@@ -3923,7 +3923,7 @@
   proname => 'macaddr8_ne', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'macaddr8 macaddr8', prosrc => 'macaddr8_ne' },
 { oid => '4119', descr => 'less-equal-greater',
-  proname => 'macaddr8_cmp', prorettype => 'int4',
+  proname => 'macaddr8_cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'macaddr8 macaddr8', prosrc => 'macaddr8_cmp' },
 { oid => '4120',
   proname => 'macaddr8_not', prorettype => 'macaddr8',
@@ -3986,8 +3986,8 @@
   proname => 'network_smaller', prorettype => 'inet',
   proargtypes => 'inet inet', prosrc => 'network_smaller' },
 { oid => '926', descr => 'less-equal-greater',
-  proname => 'network_cmp', prorettype => 'int4', proargtypes => 'inet inet',
-  prosrc => 'network_cmp' },
+  proname => 'network_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'inet inet', prosrc => 'network_cmp' },
 { oid => '927',
   proname => 'network_sub', prorettype => 'bool', proargtypes => 'inet inet',
   prosrc => 'network_sub' },
@@ -4150,8 +4150,8 @@
   proname => 'boolge', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'bool bool', prosrc => 'boolge' },
 { oid => '1693', descr => 'less-equal-greater',
-  proname => 'btboolcmp', prorettype => 'int4', proargtypes => 'bool bool',
-  prosrc => 'btboolcmp' },
+  proname => 'btboolcmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'bool bool', prosrc => 'btboolcmp' },
 
 { oid => '1688', descr => 'hash',
   proname => 'time_hash', prorettype => 'int4', proargtypes => 'time',
@@ -5547,8 +5547,8 @@
   proname => 'byteane', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'bytea bytea', prosrc => 'byteane' },
 { oid => '1954', descr => 'less-equal-greater',
-  proname => 'byteacmp', prorettype => 'int4', proargtypes => 'bytea bytea',
-  prosrc => 'byteacmp' },
+  proname => 'byteacmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'bytea bytea', prosrc => 'byteacmp' },
 { oid => '3331', descr => 'sort support',
   proname => 'bytea_sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'bytea_sortsupport' },
@@ -5706,7 +5706,7 @@
   prorettype => 'bool', proargtypes => 'timestamp interval timestamp timestamp',
   prosrc => 'select ($1, ($1 + $2)) overlaps ($3, $4)' },
 { oid => '2045', descr => 'less-equal-greater',
-  proname => 'timestamp_cmp', prorettype => 'int4',
+  proname => 'timestamp_cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'timestamp timestamp', prosrc => 'timestamp_cmp' },
 { oid => '3137', descr => 'sort support',
   proname => 'timestamp_sortsupport', prorettype => 'void',
@@ -6588,28 +6588,28 @@
   proargtypes => 'internal', prosrc => 'btbpchar_pattern_sortsupport' },
 
 { oid => '2188', descr => 'less-equal-greater',
-  proname => 'btint48cmp', prorettype => 'int4', proargtypes => 'int4 int8',
-  prosrc => 'btint48cmp' },
+  proname => 'btint48cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int4 int8', prosrc => 'btint48cmp' },
 { oid => '2189', descr => 'less-equal-greater',
-  proname => 'btint84cmp', prorettype => 'int4', proargtypes => 'int8 int4',
-  prosrc => 'btint84cmp' },
+  proname => 'btint84cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int8 int4', prosrc => 'btint84cmp' },
 { oid => '2190', descr => 'less-equal-greater',
-  proname => 'btint24cmp', prorettype => 'int4', proargtypes => 'int2 int4',
-  prosrc => 'btint24cmp' },
+  proname => 'btint24cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int2 int4', prosrc => 'btint24cmp' },
 { oid => '2191', descr => 'less-equal-greater',
-  proname => 'btint42cmp', prorettype => 'int4', proargtypes => 'int4 int2',
-  prosrc => 'btint42cmp' },
+  proname => 'btint42cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int4 int2', prosrc => 'btint42cmp' },
 { oid => '2192', descr => 'less-equal-greater',
-  proname => 'btint28cmp', prorettype => 'int4', proargtypes => 'int2 int8',
-  prosrc => 'btint28cmp' },
+  proname => 'btint28cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int2 int8', prosrc => 'btint28cmp' },
 { oid => '2193', descr => 'less-equal-greater',
-  proname => 'btint82cmp', prorettype => 'int4', proargtypes => 'int8 int2',
-  prosrc => 'btint82cmp' },
+  proname => 'btint82cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'int8 int2', prosrc => 'btint82cmp' },
 { oid => '2194', descr => 'less-equal-greater',
-  proname => 'btfloat48cmp', prorettype => 'int4',
+  proname => 'btfloat48cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'float4 float8', prosrc => 'btfloat48cmp' },
 { oid => '2195', descr => 'less-equal-greater',
-  proname => 'btfloat84cmp', prorettype => 'int4',
+  proname => 'btfloat84cmp', proleakproof => 't', prorettype => 'int4',
   proargtypes => 'float8 float4', prosrc => 'btfloat84cmp' },
 
 { oid => '2212', descr => 'I/O',
@@ -8374,8 +8374,8 @@
   proname => 'uuid_ne', proleakproof => 't', prorettype => 'bool',
   proargtypes => 'uuid uuid', prosrc => 'uuid_ne' },
 { oid => '2960', descr => 'less-equal-greater',
-  proname => 'uuid_cmp', prorettype => 'int4', proargtypes => 'uuid uuid',
-  prosrc => 'uuid_cmp' },
+  proname => 'uuid_cmp', proleakproof => 't', prorettype => 'int4',
+  proargtypes => 'uuid uuid', prosrc => 'uuid_cmp' },
 { oid => '3300', descr => 'sort support',
   proname => 'uuid_sortsupport', prorettype => 'void',
   proargtypes => 'internal', prosrc => 'uuid_sortsupport' },