为什么 try catch 语句在 TwinCAT 4024.7 中不起作用

Question

我正在尝试自 TwinCAT 4024.0 以来可用的新实现的 try/catch 语句。但是，编译时出现以下错误：

The codegenerator for the current device does not support structured exception handling.

示例代码 (source):

FUNCTION F_Calc : LREAL
VAR_INPUT
  pData     : POINTER TO ARRAY [0..9] OF LREAL;
  nElementA : INT;
  nElementB : INT;
END_VAR
VAR
  exc       : __SYSTEM.ExceptionCode;
END_VAR

__TRY
  F_Calc := pData^[nElementA] / pData^[nElementB];
__CATCH (exc)
  IF (exc = __SYSTEM.ExceptionCode.RTSEXCPT_ARRAYBOUNDS) THEN
    F_Calc := -1;
  ELSIF ((exc = __SYSTEM.ExceptionCode.RTSEXCPT_FPU_DIVIDEBYZERO) OR
         (exc = __SYSTEM.ExceptionCode.RTSEXCPT_DIVIDEBYZERO)) THEN
    F_Calc := -2;
  ELSIF (exc = __SYSTEM.ExceptionCode.RTSEXCPT_ACCESS_VIOLATION) THEN
    F_Calc := -3;
  ELSE
    F_Calc := -4;
  END_IF
__ENDTRY

Answer 1

事实证明，64 位系统尚不支持 try catch 语句。 this 文章中也提到了这一点。

来自本文关于为什么它不能在 64 位上运行的评论部分：

In the case of an exception, quite a lot happens internally. For example, the stack must be cleaned. Especially with deeply nested method calls, this can mean a lot of work. I suspect that memory management is structured under 32 bit differently than under 64 bits. However, I assume that this will be implemented for 64 bit systems in a later build.

为什么 try catch 语句在 TwinCAT 4024.7 中不起作用

Why dont the try catch statements work in TwinCAT 4024.7

try-catch

twincat