(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:4021 func: pbx_load_module  Starting AEL load process.
LOG: lev:2 file:pbx_ael.c  line:4028 func: pbx_load_module  AEL load process: calculated config file name './extensions.ael'.
LOG: lev:4 file:ael/ael.flex  line:276 func: ael_yylex  File=./extensions.ael, line=165, column=49: Mismatched '}' in expression!
LOG: lev:4 file:ael.y  line:752 func: ael_yyerror  ==== File: ./extensions.ael, Line 165, Cols: 51-51: Error: syntax error, unexpected '=', expecting ')'
LOG: lev:4 file:ael.y  line:752 func: ael_yyerror  ==== File: ./extensions.ael, Line 169, Cols: 24-24: Error: syntax error, unexpected '&'
LOG: lev:4 file:ael/ael.flex  line:276 func: ael_yylex  File=./extensions.ael, line=222, column=41: Mismatched '}' in expression!
LOG: lev:4 file:ael.y  line:752 func: ael_yyerror  ==== File: ./extensions.ael, Line 222, Cols: 43-43: Error: syntax error, unexpected '=', expecting ')'
LOG: lev:4 file:ael.y  line:752 func: ael_yyerror  ==== File: ./extensions.ael, Line 226, Cols: 16-16: Error: syntax error, unexpected '&'
LOG: lev:4 file:ael.y  line:752 func: ael_yyerror  ==== File: ./extensions.ael, Line 291, Cols: 21-28: Error: syntax error, unexpected word, expecting '(' or ';' or '=' or ':'
LOG: lev:2 file:pbx_ael.c  line:4036 func: pbx_load_module  AEL load process: parsed config file name './extensions.ael'.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 116-125: The macro dialout does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 129-168: The macro stdexten does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 184-191: The macro uvm does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 193-200: The macro bvm does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 202-207: The macro checkdnd does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 209-216: The macro checkcf does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 218-225: The macro checkcfb does not end with a return; I will insert one.
LOG: lev:3 file:pbx_ael.c  line:734 func: check_macro_returns  Warning: file ./extensions.ael, line 688-694: The macro check-psd-exists does not end with a return; I will insert one.
LOG: lev:4 file:pbx_ael.c  line:4049 func: pbx_load_module  Sorry, but 5 syntax errors and 0 semantic errors were detected. It doesn't make sense to compile.
LOG: lev:4 file:ael2_parse  line:512 func: main  0 contexts, 0 extensions, 0 priorities