dr_get_proc_address incorrectly returns base-of-library results for undefined symbols with gnu hashes

I saw this on drcachesim's -record_heap running "ls" where it claims to find "malloc" and "free" in the ls binary but returns an address at the very base of the binary:

instru_funcs_module_load for ls
dr_get_proc_address found symbol malloc at pc=0x00007f0cfda4c000
Inserted hooks for ls!malloc @0x00007f0cfda4c000 == id 0
dr_get_proc_address found symbol free at pc=0x00007f0cfda4c000
Duplicate-pc hook: ls!free == id 0

Looks like DR is not ruling out undefined symbols:

$ readelf -s -D /bin/ls 

Symbol table of `.gnu.hash' for image:
  Num Buc:    Value          Size   Type   Bind Vis      Ndx Name
  111   0: 0000000000022600     8 OBJECT  GLOBAL DEFAULT  26 __progname
  112   2: 0000000000022610     4 OBJECT  GLOBAL DEFAULT  26 optind
  113   3: 0000000000000000     0 FUNC    GLOBAL DEFAULT UND free
  114   3: 0000000000022620     8 OBJECT  WEAK   DEFAULT  26 program_invocation_name
  115   4: 0000000000022620     8 OBJECT  GLOBAL DEFAULT  26 __progname_full
  116   5: 00000000000163a0    41 FUNC    GLOBAL DEFAULT  14 _obstack_memory_used
  117   6: 00000000000225e0     8 OBJECT  GLOBAL DEFAULT  25 obstack_alloc_failed_hand
  118   6: 00000000000161b0    17 FUNC    GLOBAL DEFAULT  14 _obstack_begin
  119   7: 0000000000022640     8 OBJECT  GLOBAL DEFAULT  26 stderr
  120   8: 0000000000016330   101 FUNC    GLOBAL DEFAULT  14 _obstack_free
  121   8: 0000000000022600     8 OBJECT  WEAK   DEFAULT  26 program_invocation_short_
  122  10: 00000000000162f0    55 FUNC    GLOBAL DEFAULT  14 _obstack_allocated_p
  123  10: 0000000000022618     8 OBJECT  GLOBAL DEFAULT  26 optarg
  124  11: 00000000000161d0    21 FUNC    GLOBAL DEFAULT  14 _obstack_begin_1
  125  12: 0000000000000000     0 FUNC    WEAK   DEFAULT UND __cxa_finalize
  126  14: 00000000000161f0   251 FUNC    GLOBAL DEFAULT  14 _obstack_newchunk
  127  15: 0000000000000000     0 FUNC    GLOBAL DEFAULT UND malloc
  128  16: 0000000000022608     8 OBJECT  GLOBAL DEFAULT  26 stdout

Looking at the code, DR does the right thing for non-gnu hash lookups, but not for gnu.