# qopt-class-analysis, Qopt-class-analysis

Determines whether C++ class hierarchy information is used to analyze and resolve C++ virtual function calls at compile time.

## Syntax

Linux and macOS: | -qopt-class-analysis -qno-opt-class-analysis

Windows: | /Qopt-class-analysis /Qopt-class-analysis-

## Arguments

None

## Default

-qno-opt-class-analysis or/Qopt-class-analysis- | C++ class hierarchy information is not used to analyze and resolve C++ virtual function calls at compile time.

## Description

This option determines whether C++ class hierarchy information is used to analyze and resolve C++ virtual function calls at compile time. The option is turned on by default with the -ipo compiler option, enabling improved C++ optimization. If a C++ application contains non-standard C++ constructs, such as pointer down-casting, it may result in different behaviors.

## IDE Equivalent

None

## Alternate Options

None

Parent topic: Advanced Optimization Options