5.7.1.28 Nofallback Option

The --nofallback option can be used to ensure that the compiler is not inadvertently executed with optimizations below the that specified by the -O option.

For example, if an unlicensed compiler was requested to run with level s optimizations, without this option, it would normally revert to a lower optimization level and proceed. With this option, the compiler will instead issue an error and compilation will terminate. Thus, this option can ensure that builds are performed with a properly licensed compiler.