On Tue, Apr 05 2022, Garrit Franke wrote: > add include-what-you-use helper. > > Signed-off-by: Garrit Franke <garrit@slashdev.space> > --- > contrib/iwyu/README | 33 +++++++++++++++++++++++++++++++++ > contrib/iwyu/iwyu.sh | 2 ++ > 2 files changed, 35 insertions(+) > create mode 100644 contrib/iwyu/README > create mode 100755 contrib/iwyu/iwyu.sh > > diff --git a/contrib/iwyu/README b/contrib/iwyu/README > new file mode 100644 > index 0000000000..5e2d218602 > --- /dev/null > +++ b/contrib/iwyu/README > @@ -0,0 +1,33 @@ > +Include What You Use > +==================== > + > +Include what you use (iwyu) [1] is a tool that points out which headers a file > +should include. Moreover, it can point out includes that are not used by a file, > +which makes it especially handy for cleanup tasks. > + > +To run this script, you will need iwyu to be installed on your system. > + > +The "iwyu.sh" script runs iwyu on a given object and omits mandatory headers > +defined in "Documentation/CodingGuidelines". > + > +Example usage: > + > + ./contrib/iwyu/iwyu.sh diff.o > + > +This yields: > + > + diff.c should remove these lines: > + - #include "attr.h" // lines 13-13 > + - #include "submodule-config.h" // lines 18-18 > + > +In its current form, this script should not be used to auto-generate patches, > +since there are still some false-positives that only a human can resolve. It is > +meant as a starting point for further cleanups. It could be nice to integrate > +this as a step in our CI, but we're not quite there yet. > + > +The inspiration for this script came from this [2] email-thread. > + > +Garrit Franke <garrit@slashdev.space> > + > +[1]: https://github.com/include-what-you-use/include-what-you-use > +[2]: https://lore.kernel.org/all/220401.8635ixp3f4.gmgdl@xxxxxxxxxxxxxxxxxxx/#t > \ No newline at end of file Note the "No newline at end of file" warnings, new files should have \n at the end. > diff --git a/contrib/iwyu/iwyu.sh b/contrib/iwyu/iwyu.sh > new file mode 100755 > index 0000000000..3ef8639eae > --- /dev/null > +++ b/contrib/iwyu/iwyu.sh > @@ -0,0 +1,2 @@ > +make $1 CC=include-what-you-use CFLAGS="-Xiwyu --verbose=1" 2>&1 \ > +| grep -v -E -e '^#include <' -e '^#include "(cache|git-compat-util|gettext)\.h"' > \ No newline at end of file So that's just my one-line hack as-is (well, bisect.co replaced with $1) :) I think if we integrate some IWYU spport support that this is a rather dead end to pursue. A much better way would be to just do ("REAL_CC" is already understood by sparse): REAL_CC=gcc make CC=contrib/iwyu.sh I.e. we shouldn't run make and then parse its output, but to have make run a CC which wraps our REAL_CC. Then you could either have it "really" compile, as e.g. the "sparse" wrapper can do (note: note our sparse target but cgcc), or run whatever "make" target, and then only having to parse the output of iwyu, not iwyu+make. Also, it looks like iwyu is a nicely API'd python library, so trying to parse its output is probably a dead end too, can't we just ship a trivial API-using script for it that gets all this as nicely machine-readable data? Or, if you look at iwyu.git its own source tree has a fix_includes.py which seems to do that, *and* be able to "fix" the includes for you. All of that is just stuff I didn't have time to poke at when posting a quick reply in the original thread, but hopefully someone turning this into a series of patches will :) $ python3 fix_includes.py -h Usage: fix_includes.py [options] [filename] ... < <output from include-what-you-use script> OR fix_includes.py -s [other options] <filename> ... fix_includes.py reads the output from the include-what-you-use script on stdin -- run with --v=1 (default) verbose or above -- and, unless --sort_only or --dry_run is specified, modifies the files mentioned in the output, removing their old #include lines and replacing them with the lines given by the include_what_you_use script. It also sorts the #include and forward-declare lines.
