diff --git a/disas/arm.c b/disas/arm.c
index 93c650344c..27396dd3e1 100644
--- a/disas/arm.c
+++ b/disas/arm.c
@@ -3901,9 +3901,9 @@ print_insn_arm (bfd_vma pc, struct disassemble_info *info)
 
       status = info->read_memory_func (pc, (bfd_byte *)b, 4, info);
       if (little)
-	given = (b[0]) | (b[1] << 8) | (b[2] << 16) | (b[3] << 24);
+	given = (b[0]) | (b[1] << 8) | (b[2] << 16) | ((unsigned)b[3] << 24);
       else
-	given = (b[3]) | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
+	given = (b[3]) | (b[2] << 8) | (b[1] << 16) | ((unsigned)b[0] << 24);
     }
   else
     {