On Sat, 2019-03-16 at 21:49 +0200, Baruch Siach wrote: > Hi Joe, > > 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.