diff --git a/dwz.c b/dwz.c
index 308bcba..a6ea5ec 100644
--- a/dwz.c
+++ b/dwz.c
@@ -3580,7 +3580,14 @@ checksum_die (DSO *dso, dw_cu_ref cu, dw_die_ref top_die, dw_die_ref die)
 	  ptr += ptr_size;
 	  break;
 	case DW_FORM_flag_present:
+	  break;
 	case DW_FORM_implicit_const:
+	  if (!handled && die->die_ck_state != CK_BAD)
+	    {
+	      handled = true;
+	      die->u.p1.die_hash
+		= iterative_hash_object (t->values[i], die->u.p1.die_hash);
+	    }
 	  break;
 	case DW_FORM_flag:
 	case DW_FORM_data1:
@@ -4837,7 +4844,11 @@ die_eq_1 (dw_cu_ref cu1, dw_cu_ref cu2,
 	  ptr2 += ptr_size;
 	  break;
 	case DW_FORM_flag_present:
+	  break;
 	case DW_FORM_implicit_const:
+	  if ((!ignore_locus || old_ptr1)
+	      && t1->values[i] != t2->values[j])
+	    FAIL;
 	  break;
 	case DW_FORM_flag:
 	case DW_FORM_data1:
@@ -10456,19 +10467,18 @@ build_abbrevs_for_die (htab_t h, dw_cu_ref cu, dw_die_ref die,
 		    case DW_FORM_data4: value = read_32 (ptr); break;
 		    case DW_FORM_data8: value = read_64 (ptr); break;
 		    case DW_FORM_udata: value = read_uleb128 (ptr); break;
-		    case DW_FORM_implicit_const: break;
+		    case DW_FORM_implicit_const:
+		      value = reft->values[i];
+		      break;
 		    default:
 		      error (0, 0, "Unhandled %s for %s",
 			     get_DW_FORM_str (form),
 			     get_DW_AT_str (reft->attr[i].attr));
 		      return 1;
 		    }
-		  /* Note that the value is only used for calculating the
-		     DIE size and possibly change form. Doesn't change the
-		     implicit_const from or value.  */
+		  value = line_htab_lookup (refcu, value);
 		  if (form != DW_FORM_implicit_const)
 		    {
-		      value = line_htab_lookup (refcu, value);
 		      if (value <= 0xff)
 			{
 			  form = DW_FORM_data1;
@@ -10488,7 +10498,7 @@ build_abbrevs_for_die (htab_t h, dw_cu_ref cu, dw_die_ref die,
 		  t->attr[j].attr = reft->attr[i].attr;
 		  t->attr[j].form = form;
 		  if (form == DW_FORM_implicit_const)
-		    t->values[j] = reft->values[i];
+		    t->values[j] = value;
 		  j++;
 		  continue;
 		}
@@ -12088,10 +12098,8 @@ write_die (unsigned char *ptr, dw_cu_ref cu, dw_die_ref die,
 		  update = true;
 		  break;
 		case DW_FORM_implicit_const:
-		  /* Negative means, already transformed.  */
-		  if (reft->values[i] >= 0)
-		    update = true;
-		  value = reft->values[i];
+		  /* DW_FORM_implicit_const should have been updated
+		     already when computing abbrevs.  */
 		  break;
 		default: abort ();
 		}
@@ -12104,9 +12112,6 @@ write_die (unsigned char *ptr, dw_cu_ref cu, dw_die_ref die,
 		    case DW_FORM_data2: write_16 (ptr, value); break;
 		    case DW_FORM_data4: write_32 (ptr, value); break;
 		    case DW_FORM_udata: write_uleb128 (ptr, value); break;
-		    case DW_FORM_implicit_const:
-		      reft->values[i] = -value; /* Note, negated.  */
-		      break;
 		    default: abort ();
 		    }
 		}