I’d love it just one time when I tried editing a configure.ac I didn’t end up with this sort of thing:
configure.ac:1: error: possibly undefined macro: dnl
The actual problem? In the middle of the file, I had something like:
AC_CHECK_HEADER (blah, [
dnl ** OK, found it ***
Note the extra space between the macro name and the parenthesis. Because of the extra space character, autoconf couldn’t expand the entry correctly and misinterpreted the ‘dnl’ comment and then proceeded to tell me THE FIRST PLACE IT SAW THAT STRING, which happened to be line 1 of the file.
I hate you, autotools.