traces: make closure() less verbose

[Akim Demaille]

commit 9ad7524659a340d3c8968eaa6c7ebe7e29d46031
Author: Akim Demaille <address@hidden>
Date:   Sun Apr 14 18:08:39 2019 +0200

    traces: make closure() less verbose
    
    * src/getargs.h, src/getargs.c (trace_closure): New.
    * src/closure.c (closure): Use it.

diff --git a/src/closure.c b/src/closure.c
index 385f35c4..0f46f834 100644
--- a/src/closure.c
+++ b/src/closure.c
@@ -184,7 +184,7 @@ closure_new (unsigned n)
 void
 closure (item_number const *core, size_t n)
 {
-  if (trace_flag & trace_sets)
+  if (trace_flag & trace_closure)
     closure_print ("input", core, n);
 
   bitset_zero (ruleset);
@@ -221,7 +221,7 @@ closure (item_number const *core, size_t n)
       c++;
     }
 
-  if (trace_flag & trace_sets)
+  if (trace_flag & trace_closure)
     closure_print ("output", itemset, nitemset);
 }
 
diff --git a/src/getargs.c b/src/getargs.c
index 9cd07014..8673d41c 100644
--- a/src/getargs.c
+++ b/src/getargs.c
@@ -188,6 +188,7 @@ static const char * const trace_args[] =
   "parse      - grammar parser traces",
   "automaton  - construction of the automaton",
   "bitsets    - use of bitsets",
+  "closure    - input/output of closure",
   "grammar    - reading, reducing the grammar",
   "resource   - memory consumption (where available)",
   "sets       - grammar sets: firsts, nullable etc.",
@@ -208,6 +209,7 @@ static const int trace_types[] =
   trace_parse,
   trace_automaton,
   trace_bitsets,
+  trace_closure,
   trace_grammar,
   trace_resource,
   trace_sets,
diff --git a/src/getargs.h b/src/getargs.h
index f630d0f5..2037c00a 100644
--- a/src/getargs.h
+++ b/src/getargs.h
@@ -103,6 +103,7 @@ enum trace
     trace_m4        = 1 << 10, /**< M4 traces. */
     trace_muscles   = 1 << 11, /**< M4 definitions of the muscles. */
     trace_ielr      = 1 << 12, /**< IELR conversion. */
+    trace_closure   = 1 << 13, /**< Input/output of closure(). */
     trace_all       = ~0       /**< All of the above.  */
   };
 /** What debug items bison displays during its run.  */