Index: driver/handle.c
===================================================================
--- driver/handle.c	(revision 955)
+++ driver/handle.c	(working copy)
@@ -307,7 +307,9 @@
 #endif /* IS UNIX */
     stmt= (STMT FAR*) *phstmt;
     stmt->dbc= dbc;
+    pthread_mutex_lock(&stmt->dbc->lock);
     dbc->statements= list_add(dbc->statements,&stmt->list);
+    pthread_mutex_unlock(&stmt->dbc->lock);
     stmt->list.data= stmt;
     stmt->stmt_options= dbc->stmt_options;
     stmt->state= ST_UNKNOWN;
@@ -471,7 +473,9 @@
     x_free(stmt->cursor.name);
     x_free(stmt->bind);
     delete_dynamic(&stmt->params);
+    pthread_mutex_lock(&stmt->dbc->lock);
     stmt->dbc->statements= list_delete(stmt->dbc->statements,&stmt->list);
+    pthread_mutex_unlock(&stmt->dbc->lock);
 #ifndef _UNIX_
     GlobalUnlock(GlobalHandle ((HGLOBAL) hstmt));
     GlobalFree(GlobalHandle((HGLOBAL) hstmt));
Index: ChangeLog
===================================================================
--- ChangeLog	(revision 955)
+++ ChangeLog	(working copy)
@@ -5,6 +5,8 @@
   Bugs fixed:
   * Allowed connections to be enlisted in distributed transactions, even
     though the driver doesn't support them. (Bug #32727)
+  * Fixed thread synchronization bug in SQLAllocStmt()/SQLFreeStmt()
+    functions. (Bug #32857)
 
 ----