Add comments, assertions, and test cases to demonstrate that the

problem described in ticket #2742 is not a real problem. (CVS 4510)

FossilOrigin-Name: c085d6dfc0f5849113986cb2a25e64d0c95b3dfb

1 files changed, 11 insertions, 1 deletions

diff --git a/src/expr.c b/src/expr.c
index f196ba19c..4f3d52779 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -12,7 +12,7 @@
 ** This file contains routines used for analyzing expressions and
 ** for generating VDBE code that evaluates expressions in SQLite.
 **
-** $Id: expr.c,v 1.314 2007/10/23 15:39:45 drh Exp $
+** $Id: expr.c,v 1.315 2007/10/23 18:55:49 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -1694,12 +1694,17 @@ static char *dup8bytes(Vdbe *v, const char *in){
 /*
 ** Generate an instruction that will put the floating point
 ** value described by z[0..n-1] on the stack.
+**
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
 */
 static void codeReal(Vdbe *v, const char *z, int n, int negateFlag){
   assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
   if( z ){
     double value;
     char *zV;
+    assert( !isdigit(z[n]) );
     sqlite3AtoF(z, &value);
     if( negateFlag ) value = -value;
     zV = dup8bytes(v, (char*)&value);
@@ -1711,11 +1716,16 @@ static void codeReal(Vdbe *v, const char *z, int n, int negateFlag){
 /*
 ** Generate an instruction that will put the integer describe by
 ** text z[0..n-1] on the stack.
+**
+** The z[] string will probably not be zero-terminated.  But the 
+** z[n] character is guaranteed to be something that does not look
+** like the continuation of the number.
 */
 static void codeInteger(Vdbe *v, const char *z, int n, int negateFlag){
   assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
   if( z ){
     int i;
+    assert( !isdigit(z[n]) );
     if( sqlite3GetInt32(z, &i) ){
       if( negateFlag ) i = -i;
       sqlite3VdbeAddOp(v, OP_Integer, i, 0);