Index: src/vdbe.c
==================================================================
--- src/vdbe.c
+++ src/vdbe.c
@@ -1062,14 +1062,11 @@
   pOp->p1 = sqlite3Strlen30(pOp->p4.z);
 
 #ifndef SQLITE_OMIT_UTF16
   if( encoding!=SQLITE_UTF8 ){
     rc = sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
-    if( rc ){
-      assert( rc==SQLITE_TOOBIG ); /* This is the only possible error here */
-      goto too_big;
-    }
+    assert( rc==SQLITE_OK || rc==SQLITE_TOOBIG );
     if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
     assert( pOut->szMalloc>0 && pOut->zMalloc==pOut->z );
     assert( VdbeMemDynamic(pOut)==0 );
     pOut->szMalloc = 0;
     pOut->flags |= MEM_Static;
@@ -1078,14 +1075,16 @@
     }
     pOp->p4type = P4_DYNAMIC;
     pOp->p4.z = pOut->z;
     pOp->p1 = pOut->n;
   }
+  testcase( rc==SQLITE_TOOBIG );
 #endif
   if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
     goto too_big;
   }
+  assert( rc==SQLITE_OK );
   /* Fall through to the next case, OP_String */
 }
   
 /* Opcode: String P1 P2 P3 P4 P5
 ** Synopsis: r[P2]='P4' (len=P1)