Intel® oneAPI DPC++/C++ Compiler Developer Guide and Reference

ID 767253
Date 9/08/2022
Public

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Document Table of Contents

ftrapuv, Qtrapuv

Initializes stack local variables to an unusual value to aid error detection.

Syntax

Linux:

-ftrapuv

Windows:

None

Arguments

None

Default

OFF

The compiler does not initialize local variables.

Description

This option initializes stack local variables to an unusual value to aid error detection. Normally, these local variables should be initialized in the application. It also unmasks the floating-point invalid exception.

The option sets any uninitialized local variables that are allocated on the stack to a value that is typically interpreted as a very large integer or an invalid address. References to these variables are then likely to cause run-time errors that can help you detect coding errors.

This option sets option -g (Linux*) and /Zi or /Z7 (Windows*), which changes the default optimization level from O2 to -O0 (Linux) or /Od (Windows). You can override this effect by explicitly specifying an O option setting.

For more details on using options -ftrapuv with compiler option O, see the article titled Don't optimize when using -ftrapuv for uninitialized variable detection.

Another way to detect uninitialized local scalar variables is by specifying keyword uninit for option check.

IDE Equivalent

Visual Studio: None

Eclipse: Run-Time > Initialize Stack Variables to an Unusual Value

Alternate Options

None

See Also