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/Oy (Frame-Pointer Omission) 

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Suppresses creation of frame pointers on the call stack.

/Oy

Remarks

This option speeds function calls, because no frame pointers need to be set up and removed. It also frees one more register, (EBP on the Intel 386 or later) for storing frequently used variables and sub-expressions.

/Oy is only available in x86 compilers.

If your code requires EBP-based addressing, you can specify the /Oy– option after the /Ox option or use optimize with the "y" and off arguments to gain maximum optimization with EBP-based addressing. The compiler detects most situations where EBP-based addressing is required (for instance, with the _alloca and setjmp functions and with structured exception handling).

The /Ox (Full Optimization) (Full Optimization) and /O1, /O2 (Minimize Size, Maximize Speed) (Fast Code) options imply /Oy. Specifying /Oy– after the /Ox, /O1, or /O2 option disables /Oy, whether it is explicit or implied.

To set this compiler option in the Visual Studio development environment

  1. Open the project's Property Pages dialog box. For details, see How to: Open Project Property Pages.

  2. Click the C/C++ folder.

  3. Click the Optimization property page.

  4. Modify the Omit Frame Pointers property.

To set this compiler option programmatically

See Also

Reference

/O Options (Optimize Code)
Compiler Options
Setting Compiler Options