沒有規則使目標'|'通過

Question

我趕上一個make錯誤neded：

make: no rule to make `|' needed by cryptest.exe 

這裏的食譜：

cryptest.exe: public_service | libcryptopp.a $(TESTOBJS) 
    $(CXX) -o $@ $(CXXFLAGS) $(TESTOBJS) ./libcryptopp.a $(LDFLAGS) $(LDLIBS) 

的|是Order-only prerequisites。僅限訂單的先決條件通常有效，所以我不確定在這種情況下會出現什麼問題。

爲什麼我收到make錯誤？

---

我對這個問題表示歉意。我以前的這個問題已經被問及過很多次了。不幸的是，Google和Bing似乎都無法使用像|。

Answer 1

僅限訂購的先決條件是GNU Make 3.80中引入的一項功能。從NEWS文件

摘錄：

Version 3.80

• A new feature exists: order-only prerequisites. These prerequisites affect the order in which targets are built, but they do not impact the rebuild/no-rebuild decision of their dependents. That is to say, they allow you to require target B be built before target A, without requiring that target A will always be rebuilt if target B is updated. Patch for this feature provided by Greg McGary <…@mcgary.org> .