|
Option |
Description |
|---|---|
|
-O0 |
Disables optimizations. |
| -O1 |
Enables options -nolib_inline and -fp*. -O1 disables inline expansion of library functions. In most cases, -O2 is recommended over -O1 because the -O2 option enables inline expansion, which helps programs that have many function calls. |
| -O2 | Equivalent to options -O1 and -fp*. Confines optimizations to the procedural level. The -O2 option is on by default. * -fp is an IA-32 option and not applicable to compilations targeted for Itanium(TM)-based systems. |
| -O3 | Builds on -O1 and -O2 by enabling high-level optimization. This level does not guarantee higher performance unless loop and memory access transformation take place. In conjunction with -axK/-xK, this switch causes the compiler to perform more aggressive data dependency analysis than for -O2. This may result in longer compilation times. |
* -fp is an IA-32 option and not applicable to compilations targeted for Itanium(TM)-based systems.