In the formal c++, there is no such term called STL, STL is never an abbreviation of Standard Library or Standard Template Library. You can also refer to another my answer here. Yes, Allocators were invented by Alexander Stepanov. But his original library has been out of date and some components are adopted by the standard library.

stl中的allocator是如何接管operator new完成內(nèi)存申請(qǐng)的工作呢？對(duì)象的內(nèi)存申請(qǐng)權(quán)是如何轉(zhuǎn)移的?
all

From n4714 23.10.10.1 allocator members

[[nodiscard]] T* allocate(size_t n);
3 Remarks: the storage is obtained by calling ::operator new (21.6.2), but it is unspecified when or how often this function is called.

另外如果在棧上生成我們的stl對(duì)象，也會(huì)經(jīng)過allocator嗎？

There is no term stack in c++(only stack unwinding, which is not relevant here), in c, there is a term called activition record. Even if speaking to implementation, the choice of call stack or register should be decided by calling convention. No matter call stack or register, it will not invoke oeprator new function.