trace: Emit a warning if tracing is built in

Built in tracing should _not_ be run if it was not set on purpose. Warn as
loud as we can in order to inform the user that they are running a version
with tracing capabilities built in.

This commit also adds a subsys stub because utlimately the logging will happen
in the init phase but because the default log file is not set in the
sys_logging init function, the stub is not useful for now.

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/src/lib/trace/trace_sys.c b/src/lib/trace/trace_sys.c
index d6e59f4c3d..2ba0258407 100644
--- a/src/lib/trace/trace_sys.c
+++ b/src/lib/trace/trace_sys.c
@@ -25,9 +25,12 @@ subsys_tracing_shutdown(void)
 }
 
 const subsys_fns_t sys_tracing = {
+  SUBSYS_DECLARE_LOCATION(),
+
   .name = "tracing",
   .supported = true,
-  .level = -85,
+  .level = TRACE_SUBSYS_LEVEL,
+
   .initialize = subsys_tracing_initialize,
   .shutdown = subsys_tracing_shutdown,
 };