__optlevel

Optimization level exported as a predefined macro.

Syntax

__optlevel0

__optlevel1

__optlevel2

__optlevel3

__optlevel4

Remarks

Using these macros, user can conditionally compile code for a particular optimization level. The following table lists the level of optimization provided by the __optlevelx macro.

Table 1. Optimization Levels
Macro	Optimization Level
`__optlevel0`	`O0`
`__optlevel1`	`O1`
`__optlevel2`	`O2`
`__optlevel3`	`O3`
`__optlevel4`	`O4`

Example

The listing below shows an example of __optlevelx macro usage.

Listing 1. Example usage of __optlevel macro

int main() 
{ 
#if __optlevel0 
... // This code compiles only if this code compiled with Optimization 
level 0 
#elif __optlevel1 
... // This code compiles only if this code compiled with Optimization 
level 1 
#elif __optlevel2 
... // This code compiles only if this code compiled with Optimization 
level 2 
#elif __optlevel3 
... // This code compiles only if this code compiled with Optimization 
level 3 
#elif __optlevel4 
... // This code compiles only if this code compiled with Optimization 
level 4 
#endif 
}