Make sure the error message handler is able to deal with NULL expression

spans. Ticket #3508. (CVS 5949)

FossilOrigin-Name: ce36b6474a62f0a5b8d82968ca9a171f7143ae31

manifest

@@ -1,5 +1,5 @@
-C Fix\stestfixture\slinking\sproblem\sby\smarking\sunix-only\ssymbol\sas\ssuch.\s(CVS\s5944)
-D 2008-11-21T23:35:03
+C Make\ssure\sthe\serror\smessage\shandler\sis\sable\sto\sdeal\swith\sNULL\sexpression\r\nspans.\sTicket\s#3508.\s(CVS\s5949)
+D 2008-11-22T18:28:51
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 0aa7bbe3be6acc4045706e3bb3fd0b8f38f4a3b5
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -147,7 +147,7 @@ F src/pcache.h f20c3e82dd6da622c3fe296170cb1801f9a2d75a
 F src/pcache1.c 2453a3e925841fdb610f39bba24def8b2ad4a908
 F src/pragma.c 539e28c90e782fa909a3b3a6849d18a9eb11a548
 F src/prepare.c fcadb25d2ad722d87103517333c825b56b79a770
-F src/printf.c ce86aed93a704938ca4d0344aaa763271842a4b0
+F src/printf.c e29d9475c63e1dbfae005b98da3a60e07b5c1ca5
 F src/random.c a87afbd598aa877e23ac676ee92fd8ee5c786a51
 F src/resolve.c 4af5391d2b4c1d6c583a6805ac6660181de4545b
 F src/select.c b296a7b53dd0b2c42ab8b67d969e2c924529008c
@@ -581,6 +581,7 @@ F test/tkt3457.test e9ca2b90f0eb1fb8be73a30d29aacb2e3abedeb9
 F test/tkt3461.test 5a63e8d8ee5ce00f076b1e2f82aba5480a0f14ed
 F test/tkt3472.test e689a687631e59c7a47d9438148115fee23b16c3
 F test/tkt3493.test 8472b3464e49a27ff7271308eec46154209e667b
+F test/tkt3508.test d55e4f0ccb4f60beef800e941d2610fc4d78ce6c
 F test/tkt35xx.test 53bca895091e968126a858ee7da186f59f328994
 F test/tokenize.test ce430a7aed48fc98301611429595883fdfcab5d7
 F test/trace.test 951cd0f5f571e7f36bf7bfe04be70f90fb16fb00
@@ -661,7 +662,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P adb0aafaa6b1ea06541f653a2559f099fb1b2795
-R 3c7efc80db23daed6cb5b409b6c656fc
-U pweilbacher
-Z 758b2b6f231b1dbf0e5a753e423bfba4
+P 2ca8b82247277baf3b81b5111988305ad5f67701
+R fed990be391c6c93b3b644fa007e1c2c
+U drh
+Z b371c8bbfae57952930a76318664c6e9

manifest.uuid

@@ -1 +1 @@
-2ca8b82247277baf3b81b5111988305ad5f67701
+ce36b6474a62f0a5b8d82968ca9a171f7143ae31

src/printf.c

@@ -5,7 +5,7 @@
 ** an historical reference.  Most of the "enhancements" have been backed
 ** out so that the functionality is now the same as standard printf().
 **
-** $Id: printf.c,v 1.96 2008/11/20 18:20:28 drh Exp $
+** $Id: printf.c,v 1.97 2008/11/22 18:28:51 drh Exp $
 **
 **************************************************************************
 **
@@ -725,7 +725,7 @@ void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
   if( N<0 ){
     N = strlen(z);
   }
-  if( N==0 ){
+  if( N==0 || z==0 ){
     return;
   }
   if( p->nChar+N >= p->nAlloc ){

test/tkt3508.test

@@ -0,0 +1,38 @@
+# 2008 November 22
+#
+# 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. 
+#
+# $Id: tkt3508.test,v 1.1 2008/11/22 18:28:51 drh Exp $
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_test tkt3508-1.1 {
+  execsql {
+    CREATE TABLE modificationsTmp (
+      SUBSTRATE_HPRD_ID VARCHAR(80),
+      SUBSTRATE_GENE_SYMBOL VARCHAR(80),
+      SUBSTRATE_ISOFORM_ID VARCHAR(80),
+      SUBSTRATE_REFSEQ_ID VARCHAR(80),
+      SITE INTEGER,
+      RESIDUE VARCHAR(80),
+      ENZYME_NAME VARCHAR(80),
+      ENZYME_HPRD_ID VARCHAR(80),
+      MODIFICATION_TYPE VARCHAR(80),
+      EXPERIMENT_TYPE VARCHAR(80),
+      REFERENCE_ID VARCHAR(80)
+    );
+    select SUBSTRATE_HPRD_ID, count(substrate_refseq_id) as c
+      from modificationsTmp where c > 1 group by SUBSTRATE_HPRD_ID;
+  }
+} {}
+
+finish_test