Index: src/vdbeapi.c
==================================================================
--- src/vdbeapi.c
+++ src/vdbeapi.c
@@ -1258,11 +1258,11 @@
   ** for a statement, then the statement will be automatically recompiled,
   ** as if there had been a schema change, on the first sqlite3_step() call
   ** following any change to the bindings of that parameter.
   */
   assert( p->isPrepareV2 || p->expmask==0 );
-  if( p->expmask & ((u32)1 << (i&0x001F)) && (i<32 || p->expmask==0xffffffff) ){
+  if( p->expmask!=0 && (p->expmask & (i>=31 ? 0x80000000 : (u32)1<<i))!=0 ){
     p->expired = 1;
   }
   return SQLITE_OK;
 }
 

Index: src/vdbeaux.c
==================================================================
--- src/vdbeaux.c
+++ src/vdbeaux.c
@@ -4550,12 +4550,12 @@
 ** to sqlite3_reoptimize() that re-preparing the statement may result
 ** in a better query plan.
 */
 void sqlite3VdbeSetVarmask(Vdbe *v, int iVar){
   assert( iVar>0 );
-  if( iVar>32 ){
-    v->expmask = 0xffffffff;
+  if( iVar>=32 ){
+    v->expmask |= 0x80000000;
   }else{
     v->expmask |= ((u32)1 << (iVar-1));
   }
 }