Pre-define an empty compiler flag check macro
Pre-define an empty compiler flag check macro

If the configure host doesn't have the autoconf archive, this may let
configure proceed.

golems/ach,chen0510566/ach,golems/ach,golems/ach,chen0510566/ach,golems/ach,chen0510566/ach,chen0510566/ach,golems/ach,chen0510566/ach,chen0510566/ach,golems/ach