1 files changed, 30 insertions, 22 deletions

diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 91ac53ad0b..13eacaa8a9 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -1125,12 +1125,11 @@ error:
  * Returns true if 'b' is guaranteed to always construct
  * the same term as 'a' has matched.
  */
-static int db_match_eq_body(Eterm a, Eterm b)
+static int db_match_eq_body(Eterm a, Eterm b, int const_mode)
 {
     DECLARE_ESTACK(s);
     Uint arity;
     Eterm *ap, *bp;
-    int const_mode = 0;
     const Eterm CONST_MODE_OFF = THE_NON_VALUE;
 
     while (1) {
@@ -1224,6 +1223,7 @@ int db_match_keeps_key(int keypos, Eterm match, Eterm guard, Eterm body)
     Eterm single_body_subterm;
     Eterm single_body_subterm_key;
     Eterm* single_body_subterm_key_tpl;
+    int const_mode;
 
     if (!is_list(body)) {
         return 0;
@@ -1244,42 +1244,53 @@ int db_match_keeps_key(int keypos, Eterm match, Eterm guard, Eterm body)
         return 0;
     }
 
-    single_body_term_tpl = tuple_val(single_body_term);
-    if (arityval(*single_body_term_tpl) != 1) {
-        // not the 1-element tuple we're expecting
-        return 0;
-    }
-
     match_key = db_getkey(keypos, match);
     if (!is_value(match_key)) {
         // can't get key out of match
         return 0;
     }
 
-    single_body_subterm = single_body_term_tpl[1];
+    single_body_term_tpl = tuple_val(single_body_term);
+    if (single_body_term_tpl[0] == make_arityval(2) &&
+        single_body_term_tpl[1] == am_const) {
+        /* {const, {"ets-tuple constant"}} */
+        single_body_subterm = single_body_term_tpl[2];
+        const_mode = 1;
+    }
+    else if (*single_body_term_tpl == make_arityval(1)) {
+        /* {{"ets-tuple construction"}} */
+        single_body_subterm = single_body_term_tpl[1];
+        const_mode = 0;
+    }
+    else {
+        /* not a tuple construction */
+        return 0;
+    }
+
     single_body_subterm_key = db_getkey(keypos, single_body_subterm);
     if (!is_value(single_body_subterm_key)) {
         // can't get key out of single body subterm
         return 0;
     }
 
-    if (db_match_eq_body(match_key, single_body_subterm_key)) {
+    if (db_match_eq_body(match_key, single_body_subterm_key, const_mode)) {
         /* tuple with same key is returned */
         return 1;
     }
 
-    if (!is_tuple(single_body_subterm_key)) {
-        /* can't possibly be an element instruction */
+    if (const_mode) {
+        /* constant key did not match */
         return 0;
     }
 
-    single_body_subterm_key_tpl = tuple_val(single_body_subterm_key);
-    if (arityval(*single_body_subterm_key_tpl) != 3) {
+    if (!is_tuple(single_body_subterm_key)) {
         /* can't possibly be an element instruction */
         return 0;
     }
 
-    if (single_body_subterm_key_tpl[1] == am_element &&
+    single_body_subterm_key_tpl = tuple_val(single_body_subterm_key);
+    if (single_body_subterm_key_tpl[0] == make_arityval(3) &&
+        single_body_subterm_key_tpl[1] == am_element &&
         single_body_subterm_key_tpl[3] == am_DollarUnderscore &&
         single_body_subterm_key_tpl[2] == make_small(keypos))
     {
@@ -1290,11 +1301,6 @@ int db_match_keeps_key(int keypos, Eterm match, Eterm guard, Eterm body)
     return 0;
 }
 
-/* This is used when tracing */
-Eterm erts_match_set_lint(Process *p, Eterm matchexpr) {
-    return db_match_set_lint(p, matchexpr, DCOMP_TRACE);
-}
-
 Eterm db_match_set_lint(Process *p, Eterm matchexpr, Uint flags) 
 {
     Eterm l;
@@ -2006,7 +2012,8 @@ restart:
     do_catch = 0;
     fail_label = -1;
     build_proc = psp;
-    esdp->current_process = psp;
+    if (esdp)
+        esdp->current_process = psp;
 
 #ifdef DEBUG
     ASSERT(variables == mpsp->u.variables);
@@ -2675,7 +2682,8 @@ restart:
 	    do_catch = 1;
 	    if (in_flags & ERTS_PAM_COPY_RESULT) {
 		build_proc = c_p;
-		esdp->current_process = c_p;
+                if (esdp)
+                    esdp->current_process = c_p;
 	    }
 	    break;
 	case matchHalt: