[PATCH] gdbstub: mark expected switch fall-throughs

From: Gustavo A. R. Silva
Date: Tue Feb 26 2019 - 14:16:44 EST


In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warnings:

kernel/debug/gdbstub.c: In function âgdb_serial_stubâ:
kernel/debug/gdbstub.c:1031:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (remcom_in_buffer[1] == '\0') {
^
kernel/debug/gdbstub.c:1036:3: note: here
case 'C': /* Exception passing */
^~~~
kernel/debug/gdbstub.c:1040:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (tmp == 0)
^
kernel/debug/gdbstub.c:1043:3: note: here
case 'c': /* Continue packet */
^~~~
kernel/debug/gdbstub.c:1050:4: warning: this statement may fall through [-Wimplicit-fallthrough=]
dbg_activate_sw_breakpoints();
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/debug/gdbstub.c:1052:3: note: here
default:
^~~~~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

Notice that, in this particular case, the code comment is modified
in accordance with what GCC is expecting to find.

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
kernel/debug/gdbstub.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index 7510dc687c0d..9f267b8905b4 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -1033,13 +1033,14 @@ int gdb_serial_stub(struct kgdb_state *ks)
return DBG_PASS_EVENT;
}
#endif
+ /* Fall through */
case 'C': /* Exception passing */
tmp = gdb_cmd_exception_pass(ks);
if (tmp > 0)
goto default_handle;
if (tmp == 0)
break;
- /* Fall through on tmp < 0 */
+ /* Fall through - on tmp < 0 */
case 'c': /* Continue packet */
case 's': /* Single step packet */
if (kgdb_contthread && kgdb_contthread != current) {
@@ -1048,7 +1049,7 @@ int gdb_serial_stub(struct kgdb_state *ks)
break;
}
dbg_activate_sw_breakpoints();
- /* Fall through to default processing */
+ /* Fall through - to default processing */
default:
default_handle:
error = kgdb_arch_handle_exception(ks->ex_vector,
--
2.21.0