[Bug preprocessor/83173] C preprocessor generates incorrect linemarkers

[P at draigBrady dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83173

--- Comment #7 from Pádraig Brady <P at draigBrady dot com> ---
Have been running with these patches on an extremely large code base for the
last few months, without issue