https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112586
Bug ID: 112586 Summary: [F2023] Add "A statement shall not have more than one million characters." warning Product: gcc Version: 14.0 Status: UNCONFIRMED Keywords: diagnostic Severity: normal Priority: P3 Component: fortran Assignee: unassigned at gcc dot gnu.org Reporter: burnus at gcc dot gnu.org Target Milestone: --- See also https://gcc.gnu.org/pipermail/gcc-patches/2023-November/636868.html GCC currently has a warning for: if (gfc_notification_std (GFC_STD_GNU) || pedantic) gfc_warning (0, "Limit of %d continuations exceeded in " "statement at %C", for both fixed and free form source code. This matches: Fortran 2018's "A statement shall not have more than 255 continuation lines." But Fortran 2023 now has: "A statement shall not have more than one million characters." Where a 'statement' is "A Fortran statement is a sequence of one or more complete or partial lines." - and a 'line' is: "sequence of zero or more characters". It is not completely clear to me in how far comments count; It seems as if comment lines (blank lines or blanks followed by a comment) do not count - but do in-line comments count? What about '&'? Does a (partial) line start with the first non-blank character or already at the first column? It probably ends with '\n' and ';' and neither counts. * * * The parsing is done in scanner.cc's gfc_next_char_literal — as code is reparsed, i.e. gfc_current_locus can move to older code, we cannot simply count the number of characters at "return c". BTW: As scanner.cc currently does not handle ';', which had to be added in that case. Actually, it is not quite clear to me how the counting of continuation lines works with 'gfc_current_locus = old_loc' handling. As long we only jump back in the same line, it's fine - but I expect that reparsing might cause problems with the count handling. This count is only used by warning above, but nonetheless.