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--gnu

This option enables the GNU compiler extensions supported by the ARM compiler. The version of GCC the extensions are compatible with can be determined by inspecting the predefined macros __GNUC__ and __GNUC_MINOR__.

In addition, in GNU mode, the ARM compiler emulates GCC in its conformance to the C/C++ standards, whether more or less strict.

Usage

This option can also be combined with other source language command-line options. For example, armcc --c90 --gnu.