From d3eb4faf0cc0d7a7f0492fc60f490c95066282bf Mon Sep 17 00:00:00 2001
From: Marshall Clow <marshall@idio.com>
Date: Wed, 31 Jan 2018 11:11:12 -0800
Subject: [PATCH] Fix some warnings from gcc -
 https://github.com/boostorg/dynamic_bitset/issues/19

---
 include/boost/dynamic_bitset/dynamic_bitset.hpp | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/boost/dynamic_bitset/dynamic_bitset.hpp b/include/boost/dynamic_bitset/dynamic_bitset.hpp
index 135070d..83fcb61 100644
--- a/include/boost/dynamic_bitset/dynamic_bitset.hpp
+++ b/include/boost/dynamic_bitset/dynamic_bitset.hpp
@@ -1070,7 +1070,7 @@ bool dynamic_bitset<Block, Allocator>::all() const
                 return false;
             }
         }
-        block_type const mask = ~(~static_cast<Block>(0) << extra_bits);
+        const block_type mask = (block_type(1) << extra_bits) - 1;
         if (m_highest_block() != mask) {
             return false;
         }
@@ -1940,8 +1940,7 @@ inline void dynamic_bitset<Block, Allocator>::m_zero_unused_bits()
     const block_width_type extra_bits = count_extra_bits();
 
     if (extra_bits != 0)
-        m_highest_block() &= ~(~static_cast<Block>(0) << extra_bits);
-
+        m_highest_block() &= (Block(1) << extra_bits) - 1;
 }
 
 // check class invariants
@@ -1950,7 +1949,7 @@ bool dynamic_bitset<Block, Allocator>::m_check_invariants() const
 {
     const block_width_type extra_bits = count_extra_bits();
     if (extra_bits > 0) {
-        block_type const mask = (~static_cast<Block>(0) << extra_bits);
+        const block_type mask = block_type(~0) << extra_bits;
         if ((m_highest_block() & mask) != 0)
             return false;
     }