Translations:GCC optimization/22/en

The first and most important option is. This tells the compiler what code it should produce for your processor architecture (or arch ); it says that it should produce code for a certain kind of CPU. Different CPUs have different capabilities, support different instruction sets, and have different ways of executing code. The  flag will instruct the compiler to produce code specifically for your CPU, with all its capabilities, features, instruction sets, quirks, and so on.