Hi Joe, On Sat, Mar 16 2019, Joe Perches wrote: > On Sat, 2019-03-16 at 21:49 +0200, Baruch Siach wrote: >> On Sat, Mar 16 2019, Joe Perches wrote: >> > On Sat, 2019-03-16 at 21:26 +0200, Baruch Siach wrote: >> > > Since commit ef0cc1df90f6b ("send-email: also pick up cc addresses from >> > > -by trailers") in git version 2.20, git send-email adds to cc list >> > > addresses from all *-by lines. As a side effect a line with >> > > '-Signed-off-by' is now also added to cc. This makes send-email pick >> > > lines from patches that remove patch files from the git repo. This is >> > > common in the Buildroot project that often removes (and adds) patch >> > > files that have 'Signed-off-by' in their patch description part. >> > >> > Why is such a line used and why shouldn't an author >> > of a to-be-removed patch be cc'd? >> >> These lines are currently used because the '^([a-z-]*-by)' regexp >> matches. > > That part I already understood. > > I am not a buildroot user. > >> Buildroot is a tool that build various software packages. The patches >> being removed are usually for packages that Buildroot patches to fix the >> build. These patches are often pulled from upstream git repo of >> respective package. When the package version updates, the patch is >> dropped. >> >> We don't cc patch authors when we add the patch in the first place, >> because the regexp does not match '+Signed-off-by'. I see not reason to >> cc them when we remove the patch. > > So buildroot uses '+Signed-off-by:' and '-Signed-off-by:' lines > for some internal purpose? > > Why? > > https://buildroot.org/downloads/manual/manual.html > > doesn't mention it. No. Patches to the Buildroot project often add or remove patch files. See this one for example: http://lists.busybox.net/pipermail/buildroot/2019-March/244762.html In this case 'git send-email' added Peter Korsgaard to cc because a patch file with his sign-off is removed. (mbox) Adding cc: Baruch Siach <baruch@xxxxxxxxxx> from line 'From: Baruch Siach <baruch@xxxxxxxxxx>' (body) Adding cc: Petr Vorel <petr.vorel@xxxxxxxxx> from line 'Cc: Petr Vorel <petr.vorel@xxxxxxxxx>' (body) Adding cc: Baruch Siach <baruch@xxxxxxxxxx> from line 'Signed-off-by: Baruch Siach <baruch@xxxxxxxxxx>' (body) Adding cc: Peter Korsgaard <peter@xxxxxxxxxxxxx> from line '-Signed-off-by: Peter Korsgaard <peter@xxxxxxxxxxxxx>' The same Buildroot patch also adds a patch file that carries a number of sign-off lines. But 'git send-email didn't add these addresses to cc. In both cases I see not point in adding these addresses to cc, since they have little to do with the Buildroot patch. But only patch removal triggers the regexp. baruch -- http://baruch.siach.name/blog/ ~. .~ Tk Open Systems =}------------------------------------------------ooO--U--Ooo------------{= - baruch@xxxxxxxxxx - tel: +972.52.368.4656, http://www.tkos.co.il -