# falias, Oa

Determines whether aliasing is assumed in a program.

## Syntax

Linux: | -falias -fno-alias

macOS: | -falias -fno-alias

Windows: | /Oa /Oa-

## Arguments

None

## Default

-falias or /Oa- | On Linux* and macOS*, aliasing is assumed in the program. On Windows*, aliasing is not assumed in a program.

## Description

This option determines whether aliasing is assumed in a program.

If you specify -fno-alias or /Oa, aliasing is not assumed in a program.

If you specify -falias or /Oa-, aliasing is assumed in a program. However, this may affect performance.

## IDE Equivalent

Visual Studio: None

Eclipse: Data > Assume No Aliasing in Program

Xcode: Data > Assume No Aliasing in Program

## Alternate Options

None

Parent topic: Optimization Options

## See Also

ffnalias compiler option