Those are probably the exact same identical results as nickm got originally and nothing changed in the meantime.
The posted list was manually pruned to include only those nickm was confident would be safe to remove, like all the ones starting with HAVE_ are a really safe bet. (in particular, the others like _LARGE_FILES and _POSIX_SOURCE and anything starting with an underscore is intended to be used by system headers and might be really important, or might be completely useless, or only have any effect on certain targets).
Some of these macros are used in system header files, but we can safely remove the autoconf checks for the ones that are not. I think they are:
I think I was able to clear some of the entries mentioned by nickm.
There are separate commits for each entry to make it easier to pick/drop changes if needed and also to make the review process easier. I removed checks for:
For now I'm too afraid to remove EVENT2, TCP_INFO and U_CHAR. I need to read about autoconf more to do this. Maybe I will look for some help on #tor-dev and clear the rest.
Started looking at this; still not done reviewing. The libcap check should probably remain because I'm pretty sure we're calling stuff in there, even if we're not conditionalizing based on HAVE_LIBCAP.
The libcap checks should remain. Your removal of the other checks seems safe. Feel free to force-push the branch to remove the commit with the libcap checks.
It should probably have a changes file, because these changes have a risk of causing user-visible changes if someone is attempting to build on a less-common platform.
There are some minor issues with the changes file, found by make check-changes. Please let me know if you want help with fixing it up yourself, or if you'd rather we do it for you. As a starting point, you might want to look at doc/HACKING/CodingStandards.md, scripts/maint/lintChanges.py, and the existing ChangeLog file.
./changes/ticket31699: bug number 31699 does not appear Unrecognized header: 'Minor cleanup 'Makefile:21877: recipe for target 'check-changes' failedmake[1]: *** [check-changes] Error 1
Please let me know if you want help with fixing it up yourself, or if you'd rather we do it for you.
I apologize for the late reply, busy times. Let me try to fix it on my own. I plan to contribute more to the Tor Project so it is important for me to know what's expected and understand the full workflow.
I will let you know as soon as the MR will be updated. Thanks!