In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warnings: drivers/pci/proc.c: In function ‘proc_bus_pci_ioctl’: drivers/pci/proc.c:216:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (arch_can_pci_mmap_wc()) { ^ drivers/pci/proc.c:225:2: note: here default: ^~~~~~~ drivers/pci/xen-pcifront.c: In function ‘pcifront_backend_changed’: drivers/pci/xen-pcifront.c:1105:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (xdev->state == XenbusStateClosed) ^ drivers/pci/xen-pcifront.c:1108:2: note: here case XenbusStateClosing: ^~~~ Notice that, in this particular case, the /* fall through */ comment is placed at the very bottom of the case statement, which is what GCC is expecting to find. Warning level 3 was used: -Wimplicit-fallthrough=3 This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough. Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx> --- drivers/pci/proc.c | 1 + drivers/pci/xen-pcifront.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c index 6fa1627ce08d..445b51db75b0 100644 --- a/drivers/pci/proc.c +++ b/drivers/pci/proc.c @@ -222,6 +222,7 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd, } /* If arch decided it can't, fall through... */ #endif /* HAVE_PCI_MMAP */ + /* fall through */ default: ret = -EINVAL; break; diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index eba6e33147a2..14cf0f41ecf0 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -1104,7 +1104,7 @@ static void __ref pcifront_backend_changed(struct xenbus_device *xdev, case XenbusStateClosed: if (xdev->state == XenbusStateClosed) break; - /* Missed the backend's CLOSING state -- fallthrough */ + /* fall through - Missed the backend's CLOSING state. */ case XenbusStateClosing: dev_warn(&xdev->dev, "backend going away!\n"); pcifront_try_disconnect(pdev); -- 2.21.0