### /qlibansi Compiler Option

Syntax: | Default:
/qlibansi | /qnolibansi
/qnolibansi |

Use /qlibansi to instruct the compiler that all functions with the name of an ANSI C library function are the system functions, not user-defined functions.

With /qlibansi, the optimizer may generate code that performs better because it already knows the behavior of a system function (for example, whether or not it causes side effects).

By default, the compiler does not assume that functions with the same name as ANSI C library functions are system functions.

Summary of Compiler Options