[GCC-COMPAT] Add support library for GCC's libsupc++ and libstdc++

__throw_out_of_range_fmt is implemented in libstdc++, but it is needed by libsupc++ and that would mean we would have to link all C++ code to libstdc++.

sdk/cmake/gcc.cmake

···
 execute_process(COMMAND ${GXX_EXECUTABLE} -print-file-name=libsupc++.a OUTPUT_VARIABLE LIBSUPCXX_LOCATION)
 string(STRIP ${LIBSUPCXX_LOCATION} LIBSUPCXX_LOCATION)
 set_target_properties(libsupc++ PROPERTIES IMPORTED_LOCATION ${LIBSUPCXX_LOCATION})
-# libsupc++ requires libgcc
-target_link_libraries(libsupc++ INTERFACE libgcc)
+# libsupc++ requires libgcc and stdc++compat
+target_link_libraries(libsupc++ INTERFACE libgcc stdc++compat)
 
 add_library(libmingwex STATIC IMPORTED)
 execute_process(COMMAND ${GXX_EXECUTABLE} -print-file-name=libmingwex.a OUTPUT_VARIABLE LIBMINGWEX_LOCATION)

sdk/lib/CMakeLists.txt

···
 if(MSVC)
     add_subdirectory(cpprt)
     add_subdirectory(RunTmChk)
+else()
+    add_subdirectory(gcc-compat)
 endif()
 
 add_subdirectory(delayimp)

sdk/lib/gcc-compat/CMakeLists.txt

···
+
+include_directories(
+    ${REACTOS_SOURCE_DIR}/sdk/lib/crt/include)
+
+list(APPEND SOURCE
+    __mingw_vsprintf.c
+    __throw_out_of_range_fmt.cpp
+    StringCchCopyNA.c)
+
+add_library(stdc++compat ${SOURCE})
+set_target_cpp_properties(stdc++compat WITH_EXCEPTIONS)
+add_dependencies(stdc++compat xdk)
+target_link_libraries(stdc++compat libmsvcrt)
+remove_target_compile_option(stdc++compat "$<$<AND:$<COMPILE_LANGUAGE:CXX>,$<NOT:$<IN_LIST:cppstl,$<TARGET_PROPERTY:LINK_LIBRARIES>>>>:-nostdinc>")
+target_compile_definitions(stdc++compat PRIVATE "$<$<COMPILE_LANGUAGE:CXX>:PAL_STDCPP_COMPAT>")

sdk/lib/gcc-compat/StringCchCopyNA.c

···
+/*
+ * PROJECT:     GCC c++ support library
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     StringCchCopyNA implementation
+ * COPYRIGHT:   Copyright 2024 Timo Kreuzer <[e-mail]>
+ */
+
+#include <windows.h>
+#define StringCchCopyNA _StringCchCopyNA
+#include <strsafe.h>
+
+#undef StringCchCopyNA
+
+HRESULT
+WINAPI
+StringCchCopyNA(
+    _Out_writes_(cchDest) _Always_(_Post_z_) STRSAFE_LPSTR pszDest,
+    _In_ size_t cchDest,
+    _In_reads_or_z_(cchToCopy) STRSAFE_LPCSTR pszSrc,
+    _In_ size_t cchToCopy)
+{
+    return _StringCchCopyNA(pszDest, cchDest, pszSrc, cchToCopy);
+}

sdk/lib/gcc-compat/__mingw_vsprintf.c

···
+/*
+ * PROJECT:     GCC c++ support library
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     __mingw_vsprintf implementation
+ * COPYRIGHT:   Copyright 2024 Timo Kreuzer <[e-mail]>
+ */
+
+#include <stdio.h>
+
+int __cdecl __mingw_vsprintf(char* dest, const char* format, va_list arglist)
+{
+	return vsprintf(dest, format, arglist);
+}

sdk/lib/gcc-compat/__throw_out_of_range_fmt.cpp

···
+/*
+ * PROJECT:     GCC c++ support library
+ * LICENSE:     MIT (https://spdx.org/licenses/MIT)
+ * PURPOSE:     __throw_out_of_range_fmt implementation
+ * COPYRIGHT:   Copyright 2024 Timo Kreuzer <[e-mail]>
+ */
+
+#include <stdexcept>
+#include <cstdarg>
+#include <cstring>
+#include <malloc.h>
+
+namespace std {
+
+class out_of_range_error : public exception
+{
+    char* m_msg;
+public:
+    explicit out_of_range_error(const char* msg) noexcept
+    {
+        size_t len = strlen(msg) + 1;
+        m_msg = (char*)malloc(len);
+        strcpy(m_msg, msg);
+    }
+    virtual ~out_of_range_error() { free(m_msg); };
+    virtual const char* what() const noexcept { return m_msg; }
+};
+
+void __throw_out_of_range_fmt(const char *format, ...)
+{
+    char buffer[1024];
+    va_list argptr;
+
+    va_start(argptr, format);
+    _vsnprintf(buffer, sizeof(buffer), format, argptr);
+    buffer[sizeof(buffer) - 1] = 0;
+    va_end(argptr);
+
+    throw out_of_range_error(buffer);
+}
+
+}  // namespace std