我可以讓OCaml在未捕獲的異常上產生堆棧跟蹤嗎？

Question

在Java中，當一個異常轉義main（）函數時，stacktrace被打印到控制檯。你可以讓OCaml程序做同樣的事情嗎？

Answer 1

是，編譯-g並設置OCAMLRUNPARM=b

$ cat exc.ml 
let f() : int = 
    raise End_of_file 

let g() = 
    f() + 44 

let _ = g() 
$ ocamlc -g -o exc exc.ml 
$ OCAMLRUNPARAM=b exc 
Fatal error: exception End_of_file 
Raised at file "exc.ml", line 2, characters 10-21 
Called from file "exc.ml", line 5, characters 4-8 
Called from file "exc.ml", line 7, characters 8-11 

感謝丹尼爾Bünzli的指出，如果你編譯爲本地代碼的行爲可以是不同的。這是我看到在我的系統（Mac OS X的10.9.1，OCaml的4.01.0）：

$ ocamlopt -g -o exc exc.ml 
$ OCAMLRUNPARAM=b exc 
Fatal error: exception End_of_file 
Raised by primitive operation at file "exc.ml", line 5, characters 4-8 
Called from file "exc.ml", line 7, characters 8-11 

如果關閉內聯，事情似乎工作得很好（至少在這個非常簡單的例子）：

$ ocamlopt -inline 0 -g -o exc exc.ml 
$ OCAMLRUNPARAM=b exc 
Fatal error: exception End_of_file 
Raised at file "exc.ml", line 2, characters 10-21 
Called from file "exc.ml", line 5, characters 4-8 
Called from file "exc.ml", line 7, characters 8-11