Put a limit counter on the query planner that restricts the number of

index+constraint options that can be considered for each table in a join.
This prevents certain pathological queries from taking up too much time
in the query planner.

FossilOrigin-Name: 8690b5a0cc08eeb175230de45d4ca9b9f7b9b22aeebea70b8b7151f10b130969

src/whereInt.h

@@ -402,6 +402,7 @@ struct WhereLoopBuilder {
   int nRecValid;            /* Number of valid fields currently in pRec */
 #endif
   unsigned int bldFlags;    /* SQLITE_BLDF_* flags */
+  unsigned int iPlanLimit;  /* Search limiter */
 };
 
 /* Allowed values for WhereLoopBuider.bldFlags */