add deprecation for Trigger Cache/Lookup interfaces

src/Trigger.h

@@ -25,6 +25,7 @@ namespace detail
 class Frame;
 class Stmt;
 class Expr;
+class CallExpr;
 class ID;
 class WhenInfo;
 
@@ -86,7 +87,18 @@ public:
 	// void*'s so that the value can be associated with either a CallExpr
 	// (for interpreted execution) or a C++ function (for compiled-to-C++).
 	bool Cache(const void* obj, Val* val);
-	Val* Lookup(const void*);
+	Val* Lookup(const void* obj);
+
+	[[deprecated("Remove in v5.1. Use const void* interface instead.")]] bool
+	Cache(const CallExpr* call, Val* val)
+		{
+		return Cache((const void*)call, val);
+		}
+	[[deprecated("Remove in v5.1. Use const void* interface instead.")]] Val*
+	Lookup(const CallExpr* call)
+		{
+		return Lookup((const void*)call);
+		}
 
 	// Disable this trigger completely. Needed because Unref'ing the trigger
 	// may not immediately delete it as other references may still exist.