Fix warnings

cmake/toolchains/msvc.cmake

@@ -7,7 +7,7 @@ set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>" CACHE STR
 # Compiler options.
 add_compile_options(
     /permissive-  # strict C++
-    /W3           # enable all warnings
+    /W4           # enable all warnings
     /MP           # multi-processor compilation
 )
 if("${CMAKE_GENERATOR_PLATFORM}" STREQUAL "Win32") # 32-bit

include/boost/json/basic_parser.hpp

@@ -18,6 +18,11 @@
 #include <cmath>
 #include <cstring>
 
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4127) // conditional expression is constant
+#endif
+
 /*  This file must be manually included to get the
     function template definitions for basic_parser.
 */
@@ -2242,4 +2247,8 @@ write_some(
 } // json
 } // boost
 
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
 #endif

include/boost/json/detail/counted_resource.hpp

@@ -57,7 +57,7 @@ class counted_resource_impl final
 
     bool
     do_is_equal(
-        memory_resource const& mr) const noexcept override
+        memory_resource const&) const noexcept override
     {
         // VFALCO Is always false ok?
         return false;

include/boost/json/detail/default_resource.hpp

@@ -26,7 +26,7 @@ class default_resource final
     void*
     do_allocate(
         std::size_t n,
-        std::size_t align) override
+        std::size_t) override
     {
         return ::operator new(n);
     }

include/boost/json/detail/impl/format.ipp

@@ -53,7 +53,7 @@ inline void format_two_digits( char * dest, unsigned v )
 
 inline void format_digit( char * dest, unsigned v )
 {
-    *dest = v + '0';
+    *dest = static_cast<char>( v + '0' );
 }
 
 unsigned

include/boost/json/detail/sse2.hpp

@@ -289,14 +289,14 @@ inline std::size_t count_whitespace( char const * p, std::size_t n ) noexcept
         if( m != 0 )
         {
 #if defined(__GNUC__) || defined(__clang__)
-            std::size_t n = __builtin_ffs( m ) - 1;
+            std::size_t c = __builtin_ffs( m ) - 1;
 #else
             unsigned long index;
             _BitScanForward( &index, m );
-            std::size_t n = index;
+            std::size_t c = index;
 #endif
 
-            p += n;
+            p += c;
             return p - p0;
         }
 

include/boost/json/impl/parser.ipp

@@ -442,7 +442,7 @@ on_document_end(error_code&)
 
 bool
 parser::
-on_object_begin(error_code& ec)
+on_object_begin(error_code&)
 {
     // prevent splits from exceptions
     rs_.prepare(
@@ -476,7 +476,7 @@ on_object_end(
 
 bool
 parser::
-on_array_begin(error_code& ec)
+on_array_begin(error_code&)
 {
     // prevent splits from exceptions
     rs_.prepare(

include/boost/json/impl/serializer.ipp

@@ -15,6 +15,11 @@
 #include <boost/json/detail/sse2.hpp>
 #include <ostream>
 
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable: 4127) // conditional expression is constant
+#endif
+
 namespace boost {
 namespace json {
 
@@ -797,4 +802,8 @@ operator<<( std::ostream& os, value const& jv )
 } // json
 } // boost
 
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
 #endif

include/boost/json/monotonic_resource.hpp

@@ -48,7 +48,7 @@ class monotonic_resource final
     initial_block initial_;
 
     static std::size_t const min_block_size_ = 1024;
-    static std::size_t const max_block_size_ = -1;
+    static std::size_t const max_block_size_ = std::size_t(-1);
 
     template<typename Block>
     void*

test/monotonic_resource.cpp

@@ -116,13 +116,16 @@ class monotonic_resource_test
         {
             {
                 monotonic_resource mr;
-                mr.allocate(2048);
+                auto p = mr.allocate(2048);
+                (void)p;
                 BOOST_TEST(all_alloc_in_same_block(mr, 4096, 1));
             }
             {
                 monotonic_resource mr;
-                mr.allocate(2000, 1);
-                mr.allocate(48, 1);
+                void* p;
+                p = mr.allocate(2000, 1);
+                p = mr.allocate(48, 1);
+                (void)p;
                 BOOST_TEST(all_alloc_in_same_block(mr, 4096, 1));
             }
         }

test/snippets.cpp

@@ -14,6 +14,17 @@
 
 #include "test_suite.hpp"
 
+#ifdef _MSC_VER
+# pragma warning(push)
+# pragma warning(disable: 4101)
+#elif defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunused"
+#elif defined(__GNUC__)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wunused"
+#endif
+
 namespace boost {
 namespace json {
 
@@ -101,7 +112,6 @@ usingInitLists()
             { "account-balances", { 84, 120, 126 } } };
 
         //]
-        (void)jv;
     }
 
     {
@@ -116,7 +126,6 @@ usingInitLists()
         assert( to_string(jv) == "[true,2,\"hello\",null]" );
 
         //]
-        (void)jv;
     }
 
     {
@@ -131,7 +140,6 @@ usingInitLists()
         assert( to_string(jv) == "[true,2,\"hello\",[\"bye\",null,false]]" );
 
         //]
-        (void)jv;
     }
 
     {
@@ -141,7 +149,6 @@ usingInitLists()
         value jv = { { "hello", 42 }, { "world", 43 } }; 
 
         //]
-        (void)jv;
     }
 
     {
@@ -166,10 +173,6 @@ usingInitLists()
         assert( jv2.is_array() && jv3.is_array() && jv4.is_array() );
 
         //]
-        (void)jv1;
-        (void)jv2;
-        (void)jv3;
-        (void)jv4;
     }
 
     {
@@ -186,7 +189,6 @@ usingInitLists()
         assert ( to_string(jv) == R"([["hello",42],["world",43]])" );
 
         //]
-        (void)jv;
     }
 
     {
@@ -201,13 +203,11 @@ usingInitLists()
         array ja = { { "mercury", 36 }, { "venus", 67 }, { "earth", 93 } };
 
         for (value& jv2 : ja)
-          assert( jv2.is_array() );
+            assert( jv2.is_array() );
 
         assert( to_string(ja) == "[[\"mercury\",36],[\"venus\",67],[\"earth\",93]]" );
 
         //]
-        (void)jv1;
-        (void)ja;
     }
 
     {
@@ -220,7 +220,6 @@ usingInitLists()
         assert( jo["venus"].is_array() );
 
         //]
-        (void)jo;
     }
 
     {
@@ -237,8 +236,6 @@ usingInitLists()
         assert( to_string(jv) == R"({"clients":{"john":100,"dave":500,"joe":300}})" );
 
         //]
-        (void)jo1;
-        (void)jv;
     }
 }
 
@@ -741,18 +738,20 @@ class snippets_test
     void
     run()
     {
-        (void)&usingStrings;
         usingInitLists();
-        (void)&usingArrays;
-        (void)&usingObjects;
-        (void)&usingStorage;
-        (void)&parse_fast;
-        (void)&do_json;
-        (void)&do_rpc;
-        (void)&usingParsing;
-        (void)&usingSerializing;
-        (void)&usingExchange1;
-        (void)&usingExchange2;
+
+        &usingStrings;
+        &usingArrays;
+        &usingObjects;
+        &usingStorage;
+        &parse_fast;
+        &do_json;
+        &do_rpc;
+        &usingParsing;
+        &usingSerializing;
+        &usingExchange1;
+        &usingExchange2;
+
         BOOST_TEST_PASS();
     }
 };

test/value_ref.cpp

@@ -337,15 +337,6 @@ class value_ref_test
         }
     }
 
-    struct FT
-    {
-        value
-        to_value(storage_ptr sp) const
-        {
-            return nullptr;
-        }
-    };
-
     void
     run()
     {