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10. PASCAL-style Procedure Stack Maintenance

A mismatch in calling convention is catastrophic for a running program.

Procedure begins with a standard sequence of commands,
```
    push  ebp
    mov   ebp, esp
    sub   esp, N    ; grow stack volume by N bytes
```
where N is number of bytes required for housing of local variables.
At the end of the procedure, the following commands are found:
```
    mov esp, ebp
    pop ebp
    ret M
```
Here, M is the stack volume taken for passing parameters.
Pascal approach to passing parameters requires procedure to restore stack volume occupied by its parameters:
```
    ret M  ; Pascal and __stdcall-style calling convention stack cleanup
```

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