Fix read_ranges for 32-bit long

[Joseph Myers]

bfd/dwarf2.c:read_ranges compares bfd_vma values against -1UL, which
doesn't work correctly when long is 32-bit and bfd_vma is 64-bit
(observed as "nm -l" being very slow for mingw64 host; probably causes
issues on 32-bit hosts as well as IL32LLP64 cases such as mingw64).
Fix by using (bfd_vma) -1 in place of -1UL, as done elsewhere.

---

OK to commit?

diff --git a/bfd/dwarf2.c b/bfd/dwarf2.c
index b135ef09120..22e6b467598 100644
--- a/bfd/dwarf2.c
+++ b/bfd/dwarf2.c
@@ -3688,7 +3688,7 @@ read_ranges (struct comp_unit *unit, struct arange *arange,
 
       if (low_pc == 0 && high_pc == 0)
 	break;
-      if (low_pc == -1UL && high_pc != -1UL)
+      if (low_pc == (bfd_vma) -1 && high_pc != (bfd_vma) -1)
 	base_address = high_pc;
       else
 	{

-- 
Joseph S. Myers
joseph@codesourcery.com