dwarflint: Exclude any location list entries whose expression is empty

diff --git a/dwarflint/locstats.cc b/dwarflint/locstats.cc
index 32f3010fea9e167f35bdef2a7ca40512408f54ba..ed1fd2e92eb23a4a168973f98bad8ae8a4d982e3 100644 (file)
--- a/dwarflint/locstats.cc
+++ b/dwarflint/locstats.cc
@@ -232,18 +232,46 @@ locstats::locstats (checkstack &stack, dwarflint &lint)
              dwarf::ranges ranges (find_ranges (die_stack));
              size_t length = 0;
              size_t covered = 0;
+
+             // Arbitrarily assume that there will be no more than 10
+             // expressions per address.
+             size_t nlocs = 10;
+             Dwarf_Op *exprs[nlocs];
+             size_t exprlens[nlocs];
+
              for (dwarf::ranges::const_iterator rit = ranges.begin ();
                   rit != ranges.end (); ++rit)
                {
                  Dwarf_Addr low = (*rit).first;
                  Dwarf_Addr high = (*rit).second;
                  length += high - low;
-                 /*std::cerr << std::endl << " " << low << ".." << high
-                   << std::endl;*/
+                 //std::cerr << " " << low << ".." << high << std::endl;
+
                  for (Dwarf_Addr addr = low; addr < high; ++addr)
-                   if (dwarf_getlocation_addr (locattr, addr,
-                                               NULL, NULL, 0) > 0)
-                     covered++;
+                   {
+                     int got = dwarf_getlocation_addr (locattr, addr,
+                                                       exprs, exprlens, nlocs);
+                     if (got < 0)
+                       {
+                         struct where where = WHERE (sec_info, NULL);
+                         where_reset_1 (&where, it.cu ().offset ());
+                         where_reset_2 (&where, die.offset ());
+                         wr_error (where)
+                           << "dwarf_getlocation_addr: "
+                           << dwarf_errmsg (-1) << std::endl;
+                         break;
+                       }
+
+                     // At least one expression for the address must
+                     // be of non-zero length for us to count that
+                     // address as covered.
+                     for (int i = 0; i < got; ++i)
+                       if (exprlens[i] > 0)
+                         {
+                           covered++;
+                           break;
+                         }
+                   }
                }
              coverage = 100 * covered / length;
            }