(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:3910 func: pbx_load_module  Starting AEL load process.
LOG: lev:2 file:pbx_ael.c  line:3917 func: pbx_load_module  AEL load process: calculated config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:3925 func: pbx_load_module  AEL load process: parsed config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:3928 func: pbx_load_module  AEL load process: checked config file name './extensions.ael'.
LOG: lev:3 file:pbx_ael.c  line:3813 func: ast_compile_ael2  Warning: file ./extensions.ael, line 8-13: Empty Extension!
LOG: lev:2 file:pbx_ael.c  line:3930 func: pbx_load_module  AEL load process: compiled config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:3933 func: pbx_load_module  AEL load process: merged config file name './extensions.ael'.
LOG: lev:2 file:pbx_ael.c  line:3936 func: pbx_load_module  AEL load process: verified config file name './extensions.ael'.
LOG: lev:4 file:ael2_parse  line:479 func: main  1 contexts, 0 extensions, 0 priorities