(If you find progress and other non-error messages irritating, you can use -q to suppress them)

(You can use the -w option to dump extensions.conf format to extensions.conf.aeldump)
LOG: lev:2 file:pbx_ael.c  line:115 func: pbx_load_module  Starting AEL load process.
LOG: lev:2 file:pbx_ael.c  line:128 func: pbx_load_module  AEL load process: parsed config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:131 func: pbx_load_module  AEL load process: checked config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:134 func: pbx_load_module  AEL load process: compiled config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:139 func: pbx_load_module  AEL load process: merged config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:142 func: pbx_load_module  AEL load process: verified config file name './extensions.ael'.
LOG: lev:4 file:ael2_parse  line:518 func: main  1 contexts, 7 extensions, 18 priorities