Allowing compilation on msys2

## Description
Before there was no clear way of running msys2, and even if there was, there is no guarantee of it working, well I fixed it, and added a CI, so that we can always know if it works. Furthermore I added 2 targets more: UCRT64 and CLANG64, yes, compilation with clang64 means we can also compile with clang for windows on arm :D, plus clang has better error messages overall, anyway.

## Related Issues

#17367

## Reviewers
Anyone, it's my first PR here.

.github/workflows/MSYS2.yml

@@ -0,0 +1,77 @@
+name: CI Windows (MSYS2)
+
+on:
+  push:
+  pull_request:
+  repository_dispatch:
+    types: [run_build]
+
+permissions:
+  contents: read
+
+jobs:
+  msys2-build-test:
+    strategy:
+      fail-fast: false
+      matrix:
+        sys: [MINGW64, UCRT64,CLANG64]
+    runs-on: windows-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up MSYS2
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: ${{ matrix.sys }}
+          update: true
+          install: base-devel git
+          pacboy: >-
+            gettext:p
+            gobject-introspection:p
+            graphite2:p
+            p11-kit:p
+            qt6:p
+            qt6-3d:p
+            qt6-charts:p
+            qt6-datavis3d:p
+            qt6-imageformats:p
+            qt6-location:p
+            qt6-lottie:p
+            qt6-networkauth:p
+            qt6-quick3dphysics:p
+            qt6-quicktimeline:p
+            qt6-remoteobjects:p
+            qt6-scxml:p
+            qt6-sensors:p
+            qt6-serialbus:p
+            qt6-speech:p
+            qt6-tools:p
+            qt6-translations:p
+            qt6-virtualkeyboard:p
+            qt6-webchannel:p
+            qt6-websockets:p
+            x264:p
+            cc:p
+
+      - name: Configure and build RetroArch
+        shell: msys2 {0}
+        run: |
+          echo "Building RetroArch in ${{ matrix.sys }} environment"
+          ./configure
+          make -j$(nproc)
+
+      - name: Collect DLLs and binaries
+        shell: msys2 {0}
+        run: |
+          echo "Collecting DLLs and binaries"
+          mkdir -p dist
+          cp retroarch.exe dist/
+          ldd retroarch.exe|grep $MINGW_PREFIX |awk '{print $3}'|xargs -I {} cp {} dist/
+
+      - name: Archive build artifacts
+        if: success()
+        uses: actions/upload-artifact@v4
+        with:
+          name: retroarch-${{ matrix.sys }}
+          path: dist/

Makefile.common

@@ -2648,4 +2648,32 @@ ifeq ($(HAVE_ODROIDGO2), 1)
          gfx/drivers/oga_gfx.o
 endif
 
+# Detect the operating system
+UNAME := $(shell uname -s)
+
+# Check if the system is MSYS2 (MINGW64 or MINGW32)
+ifneq ($(findstring MINGW,$(UNAME)),)
+$(info Detected MSYS2 environment)
+
+NT_VERSION := $(shell \
+  echo '#include <windows.h>' > temp.c; \
+  echo '#ifdef _WIN32_WINNT' >> temp.c; \
+  echo '#define GET_MACRO_VALUE(x) #x' >> temp.c; \
+  echo '#define EXPAND_MACRO_VALUE(x) GET_MACRO_VALUE(x)' >> temp.c; \
+  echo '#pragma message("_WIN32_WINNT=" EXPAND_MACRO_VALUE(_WIN32_WINNT))' >> temp.c; \
+  echo '#endif' >> temp.c; \
+  $(CC) -c temp.c 2>&1 | sed -n 's/^.*_WIN32_WINNT=\(0x[0-9A-Fa-f]\+\).*/\1/p'; \
+  rm -f temp.c temp.o)
+
+ifneq ($(NT_VERSION),)
+ifeq ($(shell [ $$(( $(NT_VERSION) )) -gt $$(( 0x602 )) ] && echo true),true)
+LIBS += -lxaudio2_9
+endif
+else
+$(warning Windows NT version macro (_WIN32_WINNT) is not defined.)
+endif
+
+
+endif
+
 ##################################

audio/common/mmdevice_common_inline.h

@@ -20,10 +20,6 @@
 
 /* Fix for MSYS2 increasing _WIN32_WINNT to 0x0603*/
 #if defined(__MINGW32__) || defined(__MINGW64__)
-#ifdef _WIN32_WINNT
-#undef _WIN32_WINNT
-#endif
-#define _WIN32_WINNT 0x0600
 #define WIN32_LEAN_AND_MEAN
 #else
 typedef enum EDataFlow EDataFlow;