Allows the compiler to perform optimizations that assume errno is not modified by system calls.


Read syntax diagramSkip visual syntax diagram        .-noignerrno-.
>>- -q--+-ignerrno---+-----------------------------------------><

See also #pragma options.


Some system library routines set errno when an exception occurs. This setting and subsequent side effects of errno may be ignored by specifying -qignerrno.

Specifying a -O3 or greater optimization option will also set -qignerrno. If you require both optimization and the ability to set errno, you should specify -qnoignerrno after the optimization option on the command line.

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