From: Rishabh Bhatnagar Using initcall_t in the __field macro generates the following warning with clang version 6.0: include/trace/events/initcall.h:34:3: warning: ordered comparison of function pointers ('initcall_t' (aka 'int (*)(void)') and 'initcall_t') __field macro expands to __field_ext macro which does is_signed_type check on the type argument. Since initcall_t is defined as a function pointer, using it as the type in the __field macro, leads to an ordered comparison of function pointer warning, inside the check. Using __field_struct macro avoids the issue. Link: http://lkml.kernel.org/r/1524699755-29388-1-git-send-email-rishabhb@codeaurora.org Signed-off-by: Rishabh Bhatnagar [ Added comment to why we are using field_struct() ] Signed-off-by: Steven Rostedt (VMware) --- include/trace/events/initcall.h | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/include/trace/events/initcall.h b/include/trace/events/initcall.h index 8d6cf10d27c9..eb903c3f195f 100644 --- a/include/trace/events/initcall.h +++ b/include/trace/events/initcall.h @@ -31,7 +31,11 @@ TRACE_EVENT(initcall_start, TP_ARGS(func), TP_STRUCT__entry( - __field(initcall_t, func) + /* + * Use field_struct to avoid is_signed_type() + * comparison of a function pointer + */ + __field_struct(initcall_t, func) ), TP_fast_assign( @@ -48,8 +52,12 @@ TRACE_EVENT(initcall_finish, TP_ARGS(func, ret), TP_STRUCT__entry( - __field(initcall_t, func) - __field(int, ret) + /* + * Use field_struct to avoid is_signed_type() + * comparison of a function pointer + */ + __field_struct(initcall_t, func) + __field(int, ret) ), TP_fast_assign( -- 2.17.0