add linux support to runtime build

runtime/CMakeLists.txt

@@ -1,10 +1,13 @@
 cmake_minimum_required(VERSION 3.16)
 project(mkw_recompiled)
 
-if(NOT WIN32 OR NOT MINGW OR NOT CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR
+if((NOT (WIN32 AND MINGW)) AND (NOT CMAKE_SYSTEM_NAME STREQUAL "Linux"))
+    message(FATAL_ERROR "WiiCompiled requires Windows (LLVM-MinGW) or native Linux")
+endif()
+if(NOT CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR
    NOT CMAKE_SIZEOF_VOID_P EQUAL 8 OR
    NOT CMAKE_SYSTEM_PROCESSOR MATCHES "^(AMD64|amd64|x86_64|X86_64)$")
-    message(FATAL_ERROR "WiiCompiled requires 64-bit LLVM-MinGW Clang on Windows")
+    message(FATAL_ERROR "WiiCompiled requires 64-bit Clang targeting x86_64")
 endif()
 if(NOT CMAKE_BUILD_TYPE STREQUAL "Release")
     message(FATAL_ERROR "WiiCompiled only supports Release builds")
@@ -110,12 +113,22 @@ else()
         message(FATAL_ERROR "Requested aurora-main but ${MKW_AURORA_DIR} is missing")
     endif()
     set(DAWN_ENABLE_D3D11 OFF CACHE BOOL "" FORCE)
-    set(DAWN_ENABLE_D3D12 ON CACHE BOOL "" FORCE)
+    if(WIN32)
+        set(DAWN_ENABLE_D3D12 ON CACHE BOOL "" FORCE)
+        set(TINT_BUILD_HLSL_WRITER ON CACHE BOOL "" FORCE)
+        set(DAWN_USE_WINDOWS_UI OFF CACHE BOOL "" FORCE)
+    else()
+        # Non-Windows (Linux): mirrors aurora-main's own
+        # _aurora_dawn_set_platform_backends() choice for this platform - Vulkan only, no
+        # D3D/HLSL. Kept in sync here because this project's own CMake FORCEs these cache
+        # variables before aurora-main's add_subdirectory() runs, which pre-empts aurora's
+        # auto-detection (CACHE ... INTERNAL "" without FORCE never overrides an existing value).
+        set(DAWN_ENABLE_D3D12 OFF CACHE BOOL "" FORCE)
+        set(TINT_BUILD_HLSL_WRITER OFF CACHE BOOL "" FORCE)
+    endif()
     set(DAWN_ENABLE_VULKAN ON CACHE BOOL "" FORCE)
-    set(TINT_BUILD_HLSL_WRITER ON CACHE BOOL "" FORCE)
     set(DAWN_BUILD_SAMPLES OFF CACHE BOOL "" FORCE)
     set(DAWN_BUILD_TESTS OFF CACHE BOOL "" FORCE)
-    set(DAWN_USE_WINDOWS_UI OFF CACHE BOOL "" FORCE)
 
     # Provide a tiny stub for DXProgrammableCapture when the SDK/PIX headers are
     # missing (common on MinGW). Dawn only includes the header; no symbols are

runtime/cmake/PublicProducts.cmake

@@ -77,7 +77,9 @@ target_compile_definitions(mkw_runtime_common PRIVATE
 target_link_libraries(mkw_runtime_common PRIVATE
     aurora::gx aurora::pad aurora::si aurora::vi aurora::mtx)
 target_link_libraries(mkw_runtime_common PRIVATE mkw::pugixml mkw::toml11 mkw::cryptopp)
-target_link_libraries(mkw_runtime_common PRIVATE shell32 windowsapp)
+if(WIN32)
+    target_link_libraries(mkw_runtime_common PRIVATE shell32 windowsapp)
+endif()
 if(MKW_CPPWINRT_INCLUDE_DIR)
     if(NOT EXISTS "${MKW_CPPWINRT_INCLUDE_DIR}/winrt/base.h")
         message(FATAL_ERROR
@@ -204,26 +206,28 @@ function(mkw_configure_product target)
             $<TARGET_FILE:sqlite3> $<TARGET_FILE_DIR:${target}>)
     endif()
 
-    target_link_libraries(${target} PRIVATE
-        dbghelp user32 winmm ws2_32 iphlpapi secur32 crypt32 windowsapp setupapi winusb)
+    if(WIN32)
+        target_link_libraries(${target} PRIVATE
+            dbghelp user32 winmm ws2_32 iphlpapi secur32 crypt32 windowsapp setupapi winusb)
 
-    set_target_properties(${target} PROPERTIES WIN32_EXECUTABLE TRUE)
-    foreach(runtime_dll libc++.dll libunwind.dll)
-        execute_process(
-            COMMAND "${CMAKE_CXX_COMPILER}" "--print-file-name=${runtime_dll}"
-            OUTPUT_VARIABLE runtime_dll_path
-            OUTPUT_STRIP_TRAILING_WHITESPACE)
-        if(NOT EXISTS "${runtime_dll_path}")
-            get_filename_component(mkw_compiler_bin "${CMAKE_CXX_COMPILER}" DIRECTORY)
-            set(runtime_dll_path "${mkw_compiler_bin}/${runtime_dll}")
-        endif()
-        if(NOT EXISTS "${runtime_dll_path}")
-            message(FATAL_ERROR "llvm-mingw runtime DLL not found: ${runtime_dll}")
-        endif()
-        add_custom_command(TARGET ${target} POST_BUILD
-            COMMAND ${CMAKE_COMMAND} -E copy_if_different
-                "${runtime_dll_path}" $<TARGET_FILE_DIR:${target}>)
-    endforeach()
+        set_target_properties(${target} PROPERTIES WIN32_EXECUTABLE TRUE)
+        foreach(runtime_dll libc++.dll libunwind.dll)
+            execute_process(
+                COMMAND "${CMAKE_CXX_COMPILER}" "--print-file-name=${runtime_dll}"
+                OUTPUT_VARIABLE runtime_dll_path
+                OUTPUT_STRIP_TRAILING_WHITESPACE)
+            if(NOT EXISTS "${runtime_dll_path}")
+                get_filename_component(mkw_compiler_bin "${CMAKE_CXX_COMPILER}" DIRECTORY)
+                set(runtime_dll_path "${mkw_compiler_bin}/${runtime_dll}")
+            endif()
+            if(NOT EXISTS "${runtime_dll_path}")
+                message(FATAL_ERROR "llvm-mingw runtime DLL not found: ${runtime_dll}")
+            endif()
+            add_custom_command(TARGET ${target} POST_BUILD
+                COMMAND ${CMAKE_COMMAND} -E copy_if_different
+                    "${runtime_dll_path}" $<TARGET_FILE_DIR:${target}>)
+        endforeach()
+    endif()
 
     set(MKW_WII_BOOTSTRAP_SOURCE_DIR "${MKW_RUNTIME_SOURCE_DIR}/assets/wii")
     if(NOT EXISTS "${MKW_WII_BOOTSTRAP_SOURCE_DIR}/shared2/wc24")

runtime/include/isa/ppc_isa_config.h

@@ -11,11 +11,22 @@ inline constexpr bool MkwStateFreeAbiEnabled(uint32_t) noexcept
     return true;
 }
 
+#if defined(_WIN32)
 #define MKW_PPC_FORCE_INLINE __forceinline
 #define MKW_PPC_NO_INLINE __declspec(noinline)
+#define MKW_PPC_INTERNAL_CALL __regcall
+#else
+// __forceinline/__declspec are MS-extension keywords Clang only recognizes when targeting
+// Windows (MSVC or mingw); native Linux Clang needs the GNU-attribute spellings instead.
+// __regcall has no portable non-Windows equivalent worth chasing here - the extra register
+// args it saves matter for the hot PPC interpreter loop on Windows, but plain calls are fine
+// elsewhere.
+#define MKW_PPC_FORCE_INLINE __attribute__((always_inline)) inline
+#define MKW_PPC_NO_INLINE __attribute__((noinline))
+#define MKW_PPC_INTERNAL_CALL
+#endif
 #define MKW_PPC_ALWAYS_INLINE_BODY __attribute__((always_inline))
 #define MKW_PPC_COLD __attribute__((cold))
-#define MKW_PPC_INTERNAL_CALL __regcall
 
 
 using MkwStateFreeResult2 = uint64_t __attribute__((ext_vector_type(2)));

runtime/include/memory_access.h

@@ -18,8 +18,15 @@ extern "C" {
 }
 
 namespace MemoryInline {
+#if defined(_WIN32)
 #define MKW_MEMORY_FORCE_INLINE __forceinline
 #define MKW_MEMORY_NO_INLINE __declspec(noinline)
+#else
+// See runtime/include/isa/ppc_isa_config.h for why non-Windows Clang needs the GNU-attribute
+// spellings instead of the MS-extension keywords.
+#define MKW_MEMORY_FORCE_INLINE __attribute__((always_inline)) inline
+#define MKW_MEMORY_NO_INLINE __attribute__((noinline))
+#endif
 #define MKW_MEMORY_COLD __attribute__((cold))
 inline constexpr uint32_t kPageShift = 20;
 inline constexpr uint32_t kPageSize = 1u << kPageShift;

runtime/src/host_cpu_baseline.cpp

@@ -10,7 +10,11 @@
 #include <cstdlib>
 
 #include <cpuid.h>
+#if defined(_WIN32)
 #include <windows.h>
+#else
+#include <unistd.h>
+#endif
 
 namespace {
 
@@ -137,7 +141,12 @@ bool CollectMissingBaselineFeatures(TextBuffer& missing) {
 // up yet, and fprintf(stderr, ...) faults there. Verified on this toolchain:
 // WriteFile on the raw standard-error handle and MessageBoxA both work, printf
 // does not. Anything added to this reporting path has to respect that.
+//
+// The POSIX path runs from an __attribute__((constructor)) instead, ahead of libc's own startup
+// guarantees; ::write() on the raw fd is the same kind of allocation-free, libc-init-independent
+// primitive as WriteFile is on Windows, so the same restriction is honored here.
 void WriteStdErrEarly(const char* text) {
+#if defined(_WIN32)
     const HANDLE handle = ::GetStdHandle(STD_ERROR_HANDLE);
     if (handle == nullptr || handle == INVALID_HANDLE_VALUE) {
         return;
@@ -148,6 +157,13 @@ void WriteStdErrEarly(const char* text) {
     }
     DWORD written = 0;
     ::WriteFile(handle, text, static_cast<DWORD>(length), &written, nullptr);
+#else
+    size_t length = 0;
+    while (text[length] != '\0') {
+        ++length;
+    }
+    (void)::write(STDERR_FILENO, text, length);
+#endif
 }
 
 [[noreturn]] void ReportUnsupportedCpu(const char* missing) {
@@ -168,12 +184,18 @@ void WriteStdErrEarly(const char* text) {
     WriteStdErrEarly(message.data);
     WriteStdErrEarly("\n");
 
+#if defined(_WIN32)
     ::MessageBoxA(nullptr, message.data, "WiiCompiled - Unsupported Processor",
                   MB_OK | MB_ICONERROR | MB_SETFOREGROUND | MB_TASKMODAL);
     // Leave through the OS rather than exit(): the C++ dynamic initializers
     // have not run yet, so there is no constructed program state to unwind and
     // the teardown path itself lives in AVX2 translation units.
     ::ExitProcess(1u);
+#else
+    // Same reasoning as the Windows path above: no C++ dynamic initializer has run yet, so
+    // _exit() (skips atexit/global destructors, unlike exit()) is the correct way out.
+    ::_exit(1);
+#endif
 }
 
 }  // namespace