build: Increase MS Visual Studio minimum version

Visual Studio 2022 with `/std:c++20` supports designated initializers.

Author: hebasto

build_msvc/README.md

@@ -3,7 +3,9 @@ Building Bitcoin Core with Visual Studio
 
 Introduction
 ---------------------
-Solution and project files to build Bitcoin Core with `msbuild` or Visual Studio can be found in the `build_msvc` directory. The build has been tested with Visual Studio 2022 and Visual Studio 2019 (building with earlier versions of Visual Studio should not be expected to work).
+Visual Studio 2022 is minimum required to build Bitcoin Core.
+
+Solution and project files to build with `msbuild` or Visual Studio can be found in the `build_msvc` directory.
 
 To build Bitcoin Core from the command-line, it is sufficient to only install the Visual Studio Build Tools component.
 

build_msvc/bitcoin_config.h.in

@@ -50,8 +50,8 @@
 /* Define this symbol if the consensus lib has been built */
 #define HAVE_CONSENSUS_LIB 1
 
-/* define if the compiler supports basic C++17 syntax */
-#define HAVE_CXX17 1
+/* define if the compiler supports basic C++20 syntax */
+#define HAVE_CXX20 1
 
 /* Define to 1 if you have the declaration of `be16toh', and to 0 if you
    don't. */

build_msvc/common.init.vcxproj.in

@@ -87,10 +87,10 @@
     <ClCompile>
       <WarningLevel>Level3</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <AdditionalOptions>/utf-8 /Zc:__cplusplus /std:c++17 %(AdditionalOptions)</AdditionalOptions>
+      <AdditionalOptions>/utf-8 /Zc:__cplusplus /std:c++20 %(AdditionalOptions)</AdditionalOptions>
       <DisableSpecificWarnings>4018;4244;4267;4334;4715;4805;4834</DisableSpecificWarnings>
       <TreatWarningAsError>true</TreatWarningAsError>
-      <PreprocessorDefinitions>DISABLE_DESIGNATED_INITIALIZER_ERRORS;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;_SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING;ZMQ_STATIC;NOMINMAX;WIN32;HAVE_CONFIG_H;_CRT_SECURE_NO_WARNINGS;_SCL_SECURE_NO_WARNINGS;_CONSOLE;_WIN32_WINNT=0x0601;_WIN32_IE=0x0501;WIN32_LEAN_AND_MEAN;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_SILENCE_CXX20_U8PATH_DEPRECATION_WARNING;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;_SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING;ZMQ_STATIC;NOMINMAX;WIN32;HAVE_CONFIG_H;_CRT_SECURE_NO_WARNINGS;_SCL_SECURE_NO_WARNINGS;_CONSOLE;_WIN32_WINNT=0x0601;_WIN32_IE=0x0501;WIN32_LEAN_AND_MEAN;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>..\..\src;..\..\src\minisketch\include;..\..\src\univalue\include;..\..\src\secp256k1\include;..\..\src\leveldb\include;..\..\src\leveldb\helpers\memenv;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
     <Link>

build_msvc/msvc-autogen.py

@@ -93,7 +93,7 @@ def set_properties(vcxproj_filename, placeholder, content):
 def main():
     parser = argparse.ArgumentParser(description='Bitcoin-core msbuild configuration initialiser.')
     parser.add_argument('-toolset', nargs='?', default=DEFAULT_PLATFORM_TOOLSET,
-        help='Optionally sets the msbuild platform toolset, e.g. v142 for Visual Studio 2019, or v143 for Visual Studio 2022.'
+        help='Optionally sets the msbuild platform toolset, e.g. v143 for Visual Studio 2022.'
          ' default is %s.'%DEFAULT_PLATFORM_TOOLSET)
     args = parser.parse_args()
     set_properties(os.path.join(SOURCE_DIR, '../build_msvc/common.init.vcxproj'), '@TOOLSET@', args.toolset)