lib/fuchsia/firmware_sdk/arch/arm64/sysroot/include/bits/fenv.h

#if defined(__x86_64__)
#include "x86_64/fenv.h"
#elif defined(__aarch64__)
#include "aarch64/fenv.h"
#elif defined(__riscv)
#include "riscv64/fenv.h"
#else
#error Unsupported architecture!
#endif