On 9/18/24 10:11 AM, Jakub Jelinek wrote:
Hi!
Trailing blanks is something even git diff diagnoses; while it is a coding
style issue, if it is so common that git diff diagnoses it, I think it could
be useful to various projects to check that at compile time.
Dunno if it should be included in -Wextra, currently it isn't, and due to
tons of trailing whitespace in our sources, haven't enabled it for when
building gcc itself either.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Note, git diff also diagnoses indentation with tab following space, wonder
if we couldn't have trivial warning options where one would simply ask for
checking of indentation with no tabs, just spaces vs. indentation with
tabs followed by spaces (but never tab width or more spaces in the
indentation). I think that would be easy to do also on the libcpp side.
Checking how much something should be exactly indented requires syntax
analysis (at least some limited one) and can consider columns of first token
on line, but what the exact indentation blanks were is something only libcpp
knows.
2024-09-18 Jakub Jelinek <ja...@redhat.com>
libcpp/
* include/cpplib.h (struct cpp_options): Add cpp_warn_trailing_blanks
member.
(enum cpp_warning_reason): Add CPP_W_TRAILING_BLANKS.
* internal.h (struct _cpp_line_note): Document 'B' line note.
* lex.cc (_cpp_clean_line): Add 'B' line note for trailing blanks
except for trailing whitespace after backslash. Formatting fix.
(_cpp_process_line_notes): Emit -Wtrailing-blanks diagnostics.
Formatting fixes.
(lex_raw_string): Clear type on 'B' notes.
gcc/
* doc/invoke.texi (Wtrailing-blanks): Document.
gcc/c-family/
* c.opt (Wtrailing-blanks): New option.
gcc/testsuite/
* c-c++-common/cpp/Wtrailing-blanks.c: New test.
I'd tend to think we want this and would want to (at the appropriate
time) turn it on for our builds. Better catch this nit early rather
than at commit/push time IMHO.
As for the actual review, I'm not going to be much help here. I don't
know anything about this code.
Jeff
