/Ox (Full Optimization)
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/Ox (Full Optimization)

Updated: April 2009

The /Ox compiler option produces code that favors execution speed over smaller size.


Specifying the /Ox compiler option is the same as using the following options:

/Ox is mutually exclusive from:

The /Ox compiler option also enables the Named Return Value optimization, which eliminates the copy constructor and destructor of a stack based return value. For more information, see /O1, /O2 (Minimize Size, Maximize Speed).

You can cancel out the /Ox compiler option if you specify /Oxs, which combines the /Ox compiler option with /Os (Favor Small Code). The combined options favor smaller code size.

In general, specify /O2 (Maximize Speed) instead of /Ox, and /O1 (Minimize Size) instead of /Oxs.

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 Optimization property.

To set this compiler option programmatically




April 2009

Revised style of compiler option links to display only the relevant name.

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