The OP_ResultRow opcode releases the SCopy dependences on all its registers,

as the values in those registers will not be reused.

FossilOrigin-Name: 1dc83c5d54ca2890112e735e336c209adb8d067d2f647e9f8ae5d58f84a52461

1 files changed, 9 insertions, 0 deletions

diff --git a/src/vdbe.c b/src/vdbe.c
index 40e022d62..cc999a3eb 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -1477,6 +1477,14 @@ case OP_ResultRow: {
             || (pMem[i].flags & (MEM_Str|MEM_Blob))==0 );
     sqlite3VdbeMemNulTerminate(&pMem[i]);
     REGISTER_TRACE(pOp->p1+i, &pMem[i]);
+#ifdef SQLITE_DEBUG
+    /* The registers in the result will not be used again when the
+    ** prepared statement restarts.  This is because sqlite3_column()
+    ** APIs might have caused type conversions of made other changes to
+    ** the register values.  Therefore, we can go ahead and break any
+    ** OP_SCopy dependencies. */
+    pMem[i].pScopyFrom = 0;
+#endif
   }
   if( db->mallocFailed ) goto no_mem;
 
@@ -1484,6 +1492,7 @@ case OP_ResultRow: {
     db->xTrace(SQLITE_TRACE_ROW, db->pTraceArg, p, 0);
   }
 
+
   /* Return SQLITE_ROW
   */
   p->pc = (int)(pOp - aOp) + 1;