extern_stage       11 test/correctness/extern_output_expansion.cpp extern "C" DLLEXPORT int extern_stage(halide_buffer_t *in, halide_buffer_t *out) {
extern_stage       17 test/generator/old_buffer_t_aottest.cpp extern "C" int extern_stage(buffer_t *in2, buffer_t *f, buffer_t *out) {