Tells you exactly what and at which line the problem is?

Syntax error: unmatched thing in thing from std::nonstd::__map<_Cyrillic, _$$$dollars>const basic_string<epic_mystery,mongoose_traits<char>, __default_alloc_<casual_Fridays = maybe>>

Sure, strtok is a terrible misfeature, a relic of ancient times, but it’s plainly the heritage of C, not C++ (just like e.g. strcpy). The C++ problems are things like braced initialization list having different meaning depending on the set of available constructors, or the significantly non-zero cost of various abstractions, caused by strange backward-compatible limitations of the standard/ABI definitions, or the distinctness of vector<bool> etc.

Beware the DWIM!

In one notorious incident, Warren added a DWIM feature to the command interpreter used at Xerox PARC. One day another hacker there typed delete *$ to free up some disk space. (The editor there named backup files by appending $ to the original file name, so he was trying to delete any backup files left over from old editing sessions.) It happened that there weren’t any editor backup files, so DWIM helpfully reported *$ not found, assuming you meant ‘delete *’. It then started to delete all the files on the disk!

http://www.catb.org/jargon/html/D/DWIM.html

It’s not as easy as it sounds, sometimes the screens are all wrong!! https://xkcd.com/722/

That’s against the terms of math :-)

It will not “overflow”. Signed integer overflow is undefined behavior. The compiler could remove the whole loop or do anything else imaginable (or not).

Syntax error: unmatched thing in thing from std::nonstd::__map<_Cyrillic, _$$$dollars>const basic_string< epic_mystery,mongoose_traits<char>, __default_alloc_<casual_Fridays = maybe>>

(from James Mickens’ The Night Watch, highly recommended with his other essays: https://mickens.seas.harvard.edu/wisdom-james-mickens)