tracing: trace_output.c, fix false positive compiler warning

This compiler warning:

  CC      kernel/trace/trace_output.o
 kernel/trace/trace_output.c: In function ‘register_ftrace_event’:
 kernel/trace/trace_output.c:544: warning: ‘list’ may be used uninitialized in this function

Is wrong as 'list' is always initialized - but GCC (4.3.2) does not
recognize this relationship properly.

Work around the warning by initializing the variable to NULL.

[ Impact: fix false positive compiler warning ]

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 5fc51f0f75fc03c9535b628a56d108e9a383f0cf..8bd9a2c1a46a08b0bde704e0404cf86564a8f8ca 100644 (file)
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -541,7 +541,7 @@ int register_ftrace_event(struct trace_event *event)
        INIT_LIST_HEAD(&event->list);
 
        if (!event->type) {
-               struct list_head *list;
+               struct list_head *list = NULL;
 
                if (next_event_type > FTRACE_MAX_EVENT) {