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\ > > > > + (gdm && gdm->tty_dev && gdm->port.count); }) > > > > > > Did you test this? > > > > > > see https://godbolt.org/z/cazPrrzPv > > > > > > > I don't understand the link. The patch should work as far as I can see. > > If you call GDM_TTY_READY(gdm) the first line ends up as: > struct xxx *gdm = gdm; > which shadows the parameter. > There's probably a warning about an uninitialised variable as well. Oh yeah. You're right. But you won't get any variable uninitialized warnings because int foo = foo; was the traditional way to silence GCC's uninitialized variable warnings. Smatch copied the GCC code. There are some static checkers which might complain. Sparse used to have a warning about shadow variables but it didn't trigger on this code. Not sure why. regards, dan carpenter