Proposed fix for an infinite loop bug in the WITH clause semantic analysis

logic.

FossilOrigin-Name: 028475cb17a4b50baf0e9aba9bd3403d0a5d03b0

manifest

@@ -1,5 +1,5 @@
-C Enhance\sTreeView\sto\sshow\sWITH\sclauses.\s\sAdd\san\sassert\sto\sdetect\sthe\ninfinite\sloop\sbehavior\swhen\scertain\skinds\sof\serrors\soccur\son\sa\snested\nWITH\sclause.
+C Proposed\sfix\sfor\san\sinfinite\sloop\sbug\sin\sthe\sWITH\sclause\ssemantic\sanalysis\nlogic.
-D 2015-11-07T15:19:59.796
+D 2015-11-07T17:48:21.602
 F Makefile.in 3a705bb4bd12e194212ddbdbf068310d17153cdb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 702d3e98f3afc6587a78481257f3c4c900efc3a4
@@ -340,12 +340,12 @@ F src/printf.c 0c4bcdd1c2e2521024f0a69cb5eb334f86b3652a
 F src/random.c ba2679f80ec82c4190062d756f22d0c358180696
 F src/resolve.c 1954a0f01bf65d78d7d559aea3d5c67f33376d91
 F src/rowset.c eccf6af6d620aaa4579bd3b72c1b6395d9e9fa1e
-F src/select.c f5b0518eeb623ab4e6883a04b19602e5f914cfd7
+F src/select.c 00a2a10d4298a685d0eeb05b09ef018a2bd81bf8
 F src/shell.c d25df04168d6ba5a4fa05bdbf859df667f9eb621
 F src/sqlite.h.in 3cfc86c55e57c63d86b9e1e92869e2bfb162ca8e
 F src/sqlite3.rc 992c9f5fb8285ae285d6be28240a7e8d3a7f2bad
 F src/sqlite3ext.h 4b66e3e3435da4b4c8c83696d0349f0c503b3924
-F src/sqliteInt.h a6cddd46ae93372eb3b1acd4f2f23c4de02a94d6
+F src/sqliteInt.h bc6d24460fe544323517630b1e20539146379077
 F src/sqliteLimit.h 216557999cb45f2e3578ed53ebefe228d779cb46
 F src/status.c 70912d7be68e9e2dbc4010c93d344af61d4c59ba
 F src/table.c 51b46b2a62d1b3a959633d593b89bab5e2c9155e
@@ -396,7 +396,7 @@ F src/test_vfs.c 3b65d42e18b262805716bd96178c81da8f2d9283
 F src/test_vfstrace.c bab9594adc976cbe696ff3970728830b4c5ed698
 F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9
 F src/threads.c bbfb74450643cb5372a43ad4f6cffd7e9dfcecb0
-F src/tokenize.c 338bc8f7c9dd103188952cda7964696bacac6d22
+F src/tokenize.c b05b63e224a12531813efda3bcc73e9438958745
 F src/treeview.c 78842e90c1f71269e7a73a1d4221b6fe360bab66
 F src/trigger.c 322f23aad694e8f31d384dcfa386d52a48d3c52f
 F src/update.c 40e51cd0883cb5bfd6abb7d8a7cd8aa47fab2945
@@ -1331,6 +1331,7 @@ F test/win32lock.test fbf107c91d8f5512be5a5b87c4c42ab9fdd54972
 F test/win32longpath.test 169c75a3b2e43481f4a62122510210c67b08f26d
 F test/with1.test a1e8660be88e2eb4648f8860f831d1e38b5b5443
 F test/with2.test 2b40da883658eb74ad8ad06afabe11a408e7fb87
+F test/with3.test 511bacdbe41c49cf34f9fd1bd3245fe1575bca98
 F test/withM.test e97f2a8c506ab3ea9eab94e6f6072f6cc924c991
 F test/without_rowid1.test 1a7b9bd51b899928d327052df9741d2fe8dbe701
 F test/without_rowid2.test af260339f79d13cb220288b67cd287fbcf81ad99
@@ -1400,10 +1401,7 @@ F tool/vdbe_profile.tcl 246d0da094856d72d2c12efec03250d71639d19f
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 0f5b147d1fe83c34d0fbeacc7422be94d8441bc1
+P 2040d88e877bdb69de125a047cefb4a1558e89e8
-R 62a6359affd853c29ced84c847c76120
+R 6cacd3ab17c16b2093b599a59893b257
-T *branch * infinite-with-loop-bug
-T *sym-infinite-with-loop-bug *
-T -sym-trunk *
 U drh
-Z 3b853d83f7a6a14368bd6ec3d809b3a9
+Z 3613be9f7ebbfaa0b17b40694bdae79f

manifest.uuid

@@ -1 +1 @@
-2040d88e877bdb69de125a047cefb4a1558e89e8
+028475cb17a4b50baf0e9aba9bd3403d0a5d03b0

src/select.c

@@ -4003,12 +4003,12 @@ static struct Cte *searchWith(
 ** statement with which it is associated.
 */
 void sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){
-  assert( bFree==0 || pParse->pWith==0 );
+  assert( bFree==0 || (pParse->pWith==0 && pParse->pWithToFree==0) );
   if( pWith ){
     assert( pParse->pWith!=pWith );
     pWith->pOuter = pParse->pWith;
     pParse->pWith = pWith;
-    pParse->bFreeWith = bFree;
+    if( bFree ) pParse->pWithToFree = pWith;
   }
 }
 
@@ -4101,6 +4101,7 @@ static int withExpand(
     pSavedWith = pParse->pWith;
     pParse->pWith = pWith;
     sqlite3WalkSelect(pWalker, bMayRecursive ? pSel->pPrior : pSel);
+    pParse->pWith = pWith;
 
     for(pLeft=pSel; pLeft->pPrior; pLeft=pLeft->pPrior);
     pEList = pLeft->pEList;

src/sqliteInt.h

@@ -2754,7 +2754,6 @@ struct Parse {
   int nVar;                 /* Number of '?' variables seen in the SQL so far */
   int nzVar;                /* Number of available slots in azVar[] */
   u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
-  u8 bFreeWith;             /* True if pWith should be freed with parser */
   u8 explain;               /* True if the EXPLAIN flag is found on the query */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
@@ -2781,6 +2780,7 @@ struct Parse {
   Table *pZombieTab;        /* List of Table objects to delete after code gen */
   TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
   With *pWith;              /* Current WITH clause, or NULL */
+  With *pWithToFree;        /* Free this WITH object at the end of the parse */
 };
 
 /*

src/tokenize.c

@@ -510,7 +510,7 @@ abort_parse:
     sqlite3DeleteTable(db, pParse->pNewTable);
   }
 
-  if( pParse->bFreeWith ) sqlite3WithDelete(db, pParse->pWith);
+  sqlite3WithDelete(db, pParse->pWithToFree);
   sqlite3DeleteTrigger(db, pParse->pNewTrigger);
   for(i=pParse->nzVar-1; i>=0; i--) sqlite3DbFree(db, pParse->azVar[i]);
   sqlite3DbFree(db, pParse->azVar);

test/with3.test

@@ -0,0 +1,64 @@
+# 2015-11-07
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+# This file implements regression tests for SQLite library.  The
+# focus of this file is testing the WITH clause.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set ::testprefix with3
+
+ifcapable {!cte} {
+  finish_test
+  return
+}
+
+# Test problems found by Kostya Serebryany using 
+# LibFuzzer.  (http://llvm.org/docs/LibFuzzer.html)
+#
+do_catchsql_test 1.0 {
+  WITH i(x) AS (
+    WITH j AS (SELECT 10)
+    SELECT 5 FROM t0 UNION SELECT 8 FROM m
+  )
+  SELECT * FROM i;
+} {1 {no such table: m}}
+
+# Additional test cases that came out of the work to
+# fix for Kostya's problem.
+#
+do_execsql_test 2.0 {
+ WITH
+  x1 AS (SELECT 10),
+  x2 AS (SELECT 11),
+  x3 AS (
+    SELECT * FROM x1 UNION ALL SELECT * FROM x2
+  ),
+  x4 AS (
+    WITH
+    x1 AS (SELECT 12),
+    x2 AS (SELECT 13)
+    SELECT * FROM x3
+  )
+  SELECT * FROM x4;
+
+} {10 11}
+
+do_execsql_test 2.1 {
+  CREATE TABLE t1(x);
+  WITH
+    x1(a) AS (values(100))
+  INSERT INTO t1(x)
+    SELECT * FROM (WITH x2(y) AS (SELECT * FROM x1) SELECT y+a FROM x1, x2);
+  SELECT * FROM t1;
+} {200}
+
+finish_test