On Tue, Jul 14, 2020 at 11:18 AM Lukas Bulwahn wrote: > > > On Tue, 14 Jul 2020, Mrinal Pandey wrote: > > > The usage of "capture group (...)" in the immediate condition after `&&` > > results in `$1` being uninitialized. This issues a warning "Use of > > uninitialized value $1 in regexp compilation at ./scripts/checkpatch.pl > > line 2638". > > > > I noticed this bug while running checkpatch on the set of commits from > > v5.7 to v5.8-rc1 of the kernel on the commits with a diff content in > > their commit message. > > > > This bug was introduced in the script by commit e518e9a59ec3 > > ("checkpatch: emit an error when there's a diff in a changelog"). It has > > been in the script since then. > > > > The author intended to store the match made by capture group in variable > > `$1`. This should have contained the name of the file as `[\w/]+` > matched. > > However, this couldn't be accomplished due to usage of capture group and > > `$1` in the same regular expression. > > > > Fix this by placing the capture group in the condition before `&&`. > > Thus, `$1` can be initialized to the text that capture group matches > > thereby setting it to the desired and required value. > > > > Reviewed-by: Lukas Bulwahn > > Tested-by: Lukas Bulwahn > > Signed-off-by: Mrinal Pandey > > --- > > Changes since v1: > > Add Reviewed-by and Tested-by tag > > > > > Usually, the maintainers pick up those tags when they apply a patch to > their tree, and the patch authors do not need to add those tags and resend > the patch as a new version on the mailing list. > Sir, Thank you for your insight. I'll keep this in mind. > > Mrinal, can you please go through and check the kernel documentation on > submitting patches and find the places where it is pointed out that the > maintainers usually apply those tags and the authors usually do not need > to resend a new version of the patch with the tags applied? > I read through Submitting patches and a few related pieces of documentation but couldn't infer this information. > If you cannot find such a statement in the documentation, please let us > know where it would ideally added in the documentation. We can then create > a patch for that together. > The statement might be placed under Respond to review comments and maybe it could further contain some information about how to send a new version of the patch. Thank you. > > > Lukas >