2271 - bugfix: traces cross-contaminating errors

There were several places where we push a call on to a routine without
incrementing call-stack depth, which was used to compute the depth at
which to trace an instruction. So sometimes you ended up one depth lower
than you started a call with. Do this enough times and instructions that
should be traced at level 100 end up at level 0 and pop up as errors.

Solution: since call-stack depth is only used for tracing, include it in
the trace stream and make sure we reset it along with the trace stream.
Then catch all places where we forget to increment call-stack depth and
make sure we catch such places in the future.

When I first ran into this with Caleb I thought there must be some way
that we're writing some output into the warnings result. I didn't
recognize that the spurious output as part of the trace, just at the
wrong level.

1 files changed, 5 insertions, 1 deletions

diff --git a/036call_reply.cc b/036call_reply.cc
index ccf18a2f..e2e34c06 100644
--- a/036call_reply.cc
+++ b/036call_reply.cc
@@ -25,7 +25,11 @@ case REPLY: {
   // Starting Reply
   const instruction& reply_inst = current_instruction();  // save pointer into recipe before pop
   const string& callee = current_recipe_name();
-  --Callstack_depth;
+  if (Trace_stream) {
+    trace("trace") << "reply: decrementing callstack depth from " << Trace_stream->callstack_depth << end();
+    --Trace_stream->callstack_depth;
+    assert(Trace_stream->callstack_depth >= 0);
+  }
   Current_routine->calls.pop_front();
   // just in case 'main' returns a value, drop it for now
   if (Current_routine->calls.empty()) goto stop_running_current_routine;