GCC provides support for the following built-in reduction functions if Cilk Plus is enabled. Cilk Plus can be enabled using the -fcilkplus flag.
__sec_implicit_index
__sec_reduce
__sec_reduce_add
__sec_reduce_all_nonzero
__sec_reduce_all_zero
__sec_reduce_any_nonzero
__sec_reduce_any_zero
__sec_reduce_max
__sec_reduce_min
__sec_reduce_max_ind
__sec_reduce_min_ind
__sec_reduce_mul
__sec_reduce_mutating
Further details and examples about these built-in functions are described in the Cilk Plus language manual which can be found at http://www.cilkplus.org.