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    SubjectRe: [PATCH] Silence an uninitialized variable warning
    On Wed, Dec 04, 2019 at 09:42:47PM +0300, Dan Carpenter wrote:

    > > The current code has this:
    > >
    > > static int __init syscall_enter_define_fields(struct trace_event_call *call)
    > > {
    > > struct syscall_trace_enter trace;
    > > struct syscall_metadata *meta = call->data;
    > > int ret;
    > > int i;
    > > int offset = offsetof(typeof(trace), args);
    > >
    > > ret = trace_define_field(call, SYSCALL_FIELD(int, nr, __syscall_nr),
    > > FILTER_OTHER);
    >
    > In linux-next this ret = trace_define_field() assignment is removed.
    > That was commit 60fdad00827c ("ftrace: Rework event_create_dir()").

    Yep, mea culpa.

    > > if (ret)
    > > return ret;
    > >
    > > for (i = 0; i < meta->nb_args; i++) {
    > > ret = trace_define_field(call, meta->types[i],
    > > meta->args[i], offset,
    > > sizeof(unsigned long), 0,
    > > FILTER_OTHER);
    > > offset += sizeof(unsigned long);
    > > }
    > >
    > > return ret;
    > > }
    > >
    > >
    > > How can ret possibly be uninitialized?
    >
    > I should have written this commit more carefully and verified whether
    > meta->nb_args can actually be zero instead of just assuming it was a
    > false positive...

    Right, I'm thinking this is in fact possible. We have syscalls without
    arguments (sys_sched_yield for exmaple).

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