Summarizes the ARM® compiler-specific pragmas that are extensions to the C and C++ Standards.
4.1 #pragma clang system_header.
4.2 #pragma clang diagnostic.
4.3 #pragma once.
4.4 #pragma pack(n).
4.5 #pragma unroll[(n)], #pragma unroll_completely.
4.6 #pragma weak symbol, #pragma weak symbol1 = symbol2.