When CONFIG_IPV6=n, and building with W=1:
In file included from include/trace/define_trace.h:102,
from include/trace/events/neigh.h:255,
from net/core/net-traces.c:51:
include/trace/events/neigh.h: In function ‘trace_event_raw_event_neigh_create’:
include/trace/events/neigh.h:42:34: error: variable ‘pin6’ set but not used [-Werror=unused-but-set-variable]
42 | struct in6_addr *pin6;
| ^~~~
include/trace/trace_events.h:402:11: note: in definition of macro ‘DECLARE_EVENT_CLASS’
402 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro ‘PARAMS’
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/neigh.h:23:1: note: in expansion of macro ‘TRACE_EVENT’
23 | TRACE_EVENT(neigh_create,
| ^~~~~~~~~~~
include/trace/events/neigh.h:41:9: note: in expansion of macro ‘TP_fast_assign’
41 | TP_fast_assign(
| ^~~~~~~~~~~~~~
In file included from include/trace/define_trace.h:103,
from include/trace/events/neigh.h:255,
from net/core/net-traces.c:51:
include/trace/events/neigh.h: In function ‘perf_trace_neigh_create’:
include/trace/events/neigh.h:42:34: error: variable ‘pin6’ set but not used [-Werror=unused-but-set-variable]
42 | struct in6_addr *pin6;
| ^~~~
include/trace/perf.h:51:11: note: in definition of macro ‘DECLARE_EVENT_CLASS’
51 | { assign; } \
| ^~~~~~
include/trace/trace_events.h:44:30: note: in expansion of macro ‘PARAMS’
44 | PARAMS(assign), \
| ^~~~~~
include/trace/events/neigh.h:23:1: note: in expansion of macro ‘TRACE_EVENT’
23 | TRACE_EVENT(neigh_create,
| ^~~~~~~~~~~
include/trace/events/neigh.h:41:9: note: in expansion of macro ‘TP_fast_assign’
41 | TP_fast_assign(
| ^~~~~~~~~~~~~~
Indeed, the variable pin6 is declared and initialized unconditionally,
while it is only used and needlessly re-initialized when support for
IPv6 is enabled.
Fix this by dropping the unused variable initialization, and moving the
variable declaration inside the existing section protected by a check
for CONFIG_IPV6.
Fixes: fc651001d2 ("neighbor: Add tracepoint to __neigh_create")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Simon Horman <horms@kernel.org> # build-tested
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2915240edd