Build: Add support to switch the C++ standard

Author: Pagghiu

README.md

@@ -58,7 +58,6 @@ Each library is color-coded to signal its status:
 🟩 Usable (a reasonable set of useful features has been implemented)  
 
 <picture>
-  <source media="(prefers-color-scheme: dark)" srcset="https://pagghiu.github.io/images/dependencies/SaneCppLibrariesDependenciesDark.svg">
   <img alt="Sane C++ Libraries dependencies" src="https://pagghiu.github.io/images/dependencies/SaneCppLibrariesDependencies.svg">
 </picture>
 

Tools/SC-build/Build.h

@@ -167,6 +167,48 @@ struct Warning
     Warning(State state, uint32_t number) : state(state), type(MSVCWarning), number(number) {}
 };
 
+struct CppStandard
+{
+    enum Type
+    {
+        CPP11,
+        CPP14,
+        CPP17,
+        CPP20,
+        CPP23,
+    };
+
+    /// @brief Get StringView from CppStandard::Type
+    static constexpr StringView toString(Type type)
+    {
+        switch (type)
+        {
+        case CPP11: return "c++11";
+        case CPP14: return "c++14";
+        case CPP17: return "c++17";
+        case CPP20: return "c++20";
+        case CPP23: return "c++23";
+        }
+        Assert::unreachable();
+    }
+
+    /// @brief Get MSVC LanguageStandard value from CppStandard::Type (e.g., stdcpp14)
+    static constexpr StringView toMSVCString(Type type)
+    {
+        switch (type)
+        {
+        case CPP11: return "stdcpp11";
+        case CPP14: return "stdcpp14";
+        case CPP17: return "stdcpp17";
+        case CPP20: return "stdcpp20";
+        case CPP23: return "stdcpp23";
+        }
+        Assert::unreachable();
+    }
+
+    /// @brief Get Makefile -std= flag from CppStandard::Type
+    static StringView toMakefileFlag(Type type) { return toString(type); }
+};
 /// @brief Compile flags (include paths, preprocessor defines etc.)
 struct CompileFlags
 {
@@ -182,6 +224,8 @@ struct CompileFlags
     Parameter<bool> enableStdCpp     = false; ///< Enable and include C++ Standard Library
     Parameter<bool> enableCoverage   = false; ///< Enables code coverage instrumentation
 
+    Parameter<CppStandard::Type> cppStandard = CppStandard::CPP14; ///< C++ language standard version
+
     /// @brief Merges opinions about flags into target flags
     /// @param opinions Opinions about flags from strongest to weakest
     /// @param flags Output flags

Tools/SC-build/Build.inl

@@ -35,6 +35,7 @@ SC::Result SC::Build::CompileFlags::merge(Span<const CompileFlags*> opinions, Co
     Internal::writeStrongest(&CompileFlags::enableExceptions, opinions, flags);
     Internal::writeStrongest(&CompileFlags::enableStdCpp, opinions, flags);
     Internal::writeStrongest(&CompileFlags::enableCoverage, opinions, flags);
+    Internal::writeStrongest(&CompileFlags::cppStandard, opinions, flags);
 
     // TODO: Implement ability to "remove" paths from stronger opinions
     for (const CompileFlags* opinion : opinions)
@@ -167,7 +168,7 @@ bool SC::Build::Project::addPresetConfiguration(Configuration::Preset preset, co
 
 SC::Build::Configuration* SC::Build::Project::getConfiguration(StringView configurationName)
 {
-    size_t index;
+    size_t index = 0;
     if (configurations.find([=](auto it) { return it.name == configurationName; }, &index))
     {
         return &configurations[index];

Tools/SC-build/BuildWriterMakefile.inl

@@ -573,8 +573,8 @@ endif
     {
         SC_COMPILER_WARNING_PUSH_UNUSED_RESULT;
 
-        // TODO: De-hardcode -std=c++14
-        builder.append("\n{0}_COMMON_CXXFLAGS := -std=c++14", makeTarget);
+        builder.append("\n{0}_COMMON_CXXFLAGS := -std={1}", makeTarget,
+                       CppStandard::toString(compileFlags.cppStandard));
 
         if (not compileFlags.enableRTTI)
         {

Tools/SC-build/BuildWriterVisualStudio.inl

@@ -318,6 +318,11 @@ struct SC::Build::ProjectWriter::WriterVisualStudio
         }
 
         builder.append("      <MultiProcessorCompilation>true</MultiProcessorCompilation>\n");
+        if (compileFlags.cppStandard != CppStandard::CPP14)
+        {
+            builder.append("      <LanguageStandard>{}</LanguageStandard>\n",
+                           CppStandard::toMSVCString(compileFlags.cppStandard));
+        }
         builder.append("    </ClCompile>\n");
         builder.append("    <Link>\n");
         switch (project.targetType)

Tools/SC-build/BuildWriterXCode.inl

@@ -619,16 +619,17 @@ struct SC::Build::ProjectWriter::WriterXCode
         return true;
     }
 
-    [[nodiscard]] bool writeCommonOptions(StringBuilder& builder, const Project& project)
+    [[nodiscard]] bool writeCommonOptions(StringBuilder& builder, const Project& project, CppStandard::Type cppStandard)
     {
         SC_COMPILER_WARNING_PUSH_UNUSED_RESULT;
         builder.append(R"delimiter(
                        ALWAYS_SEARCH_USER_PATHS = NO;
                        ASSETCATALOG_COMPILER_GENERATE_SWIFT_ASSET_SYMBOL_EXTENSIONS = NO;
                        CLANG_ANALYZER_NONNULL = YES;
                        CLANG_ANALYZER_NUMBER_OBJECT_CONVERSION = YES_AGGRESSIVE;
-                       CLANG_CXX_LANGUAGE_STANDARD = "c++14";
-                       CURRENT_PROJECT_VERSION = 1;)delimiter");
+                       CLANG_CXX_LANGUAGE_STANDARD = "{0}";
+                       CURRENT_PROJECT_VERSION = 1;)delimiter",
+                       CppStandard::toString(cppStandard));
 
         if (project.targetType == TargetType::GUIApplication)
         {
@@ -741,7 +742,7 @@ struct SC::Build::ProjectWriter::WriterXCode
             buildSettings = {{)delimiter",
             xcodeObject.referenceHash.view(), xcodeObject.name.view());
 
-        writeCommonOptions(builder, project);
+        writeCommonOptions(builder, project, compileFlags.cppStandard);
         writeDirectories(builder, configuration);
 
         if (compileFlags.enableRTTI)