From 7f7451fbacf36971bf9d73a0fdd27b9a83a9d90f Mon Sep 17 00:00:00 2001
From: "Serge S. Gulin" <gulin.serge@gmail.com>
Date: Fri, 3 Jan 2025 22:44:23 +0300
Subject: [PATCH] Add support for Windows Aarch64

Co-authored-by: Cheng Shao <terrorjack@type.dance>
---
 Cabal/src/Distribution/Compat/Environment.hs              | 2 +-
 Cabal/src/Distribution/Simple/Build/PathsModule.hs        | 1 +
 Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs      | 5 +++--
 cabal-dev-scripts/src/GenPathsModule.hs                   | 1 +
 .../src/Distribution/Client/Compat/ExecutablePath.hs      | 2 +-
 changelog.d/pr-10705                                      | 8 ++++++++
 6 files changed, 15 insertions(+), 4 deletions(-)
 create mode 100644 changelog.d/pr-10705

diff --git a/Cabal/src/Distribution/Compat/Environment.hs b/Cabal/src/Distribution/Compat/Environment.hs
index ffe278bcc54..8cc9d582ad9 100644
--- a/Cabal/src/Distribution/Compat/Environment.hs
+++ b/Cabal/src/Distribution/Compat/Environment.hs
@@ -63,7 +63,7 @@ setEnv_ key value = withCWString key $ \k -> withCWString value $ \v -> do
 {- FOURMOLU_DISABLE -}
 # if defined(i386_HOST_ARCH)
 #  define WINDOWS_CCONV stdcall
-# elif defined(x86_64_HOST_ARCH)
+# elif defined(x86_64_HOST_ARCH) || defined(aarch64_HOST_ARCH)
 #  define WINDOWS_CCONV ccall
 # else
 #  error Unknown mingw32 arch
diff --git a/Cabal/src/Distribution/Simple/Build/PathsModule.hs b/Cabal/src/Distribution/Simple/Build/PathsModule.hs
index 892e5bd384f..dc8348f6396 100644
--- a/Cabal/src/Distribution/Simple/Build/PathsModule.hs
+++ b/Cabal/src/Distribution/Simple/Build/PathsModule.hs
@@ -51,6 +51,7 @@ generatePathsModule pkg_descr lbi clbi =
       , Z.zIsWindows = isWindows
       , Z.zIsI386 = buildArch == I386
       , Z.zIsX8664 = buildArch == X86_64
+      , Z.zIsAarch64 = buildArch == AArch64
       , Z.zNot = not
       , Z.zManglePkgName = showPkgName
       , Z.zPrefix = show flat_prefix
diff --git a/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs b/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
index ad979c42951..a6ecb5005a2 100644
--- a/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
+++ b/Cabal/src/Distribution/Simple/Build/PathsModule/Z.hs
@@ -12,6 +12,7 @@ data Z
          zIsWindows :: Bool,
          zIsI386 :: Bool,
          zIsX8664 :: Bool,
+         zIsAarch64 :: Bool,
          zPrefix :: FilePath,
          zBindir :: FilePath,
          zLibdir :: FilePath,
@@ -278,13 +279,13 @@ render z_root = execWriter $ do
           tell "  c_GetModuleFileName :: Ptr () -> CWString -> Int32 -> IO Int32\n"
           return ()
         else do
-          if (zIsX8664 z_root)
+          if (zIsX8664 z_root || zIsAarch64 z_root)
           then do
             tell "foreign import ccall unsafe \"windows.h GetModuleFileNameW\"\n"
             tell "  c_GetModuleFileName :: Ptr () -> CWString -> Int32 -> IO Int32\n"
             return ()
           else do
-            tell "-- win32 supported only with I386, X86_64\n"
+            tell "-- win32 supported only with I386, X86_64, Aarch64\n"
             tell "c_GetModuleFileName :: Ptr () -> CWString -> Int32 -> IO Int32\n"
             tell "c_GetModuleFileName  = _\n"
             return ()
diff --git a/cabal-dev-scripts/src/GenPathsModule.hs b/cabal-dev-scripts/src/GenPathsModule.hs
index 46ef779e2af..ca7380c74df 100644
--- a/cabal-dev-scripts/src/GenPathsModule.hs
+++ b/cabal-dev-scripts/src/GenPathsModule.hs
@@ -32,6 +32,7 @@ $(capture "decls" [d|
         , zIsWindows                  :: Bool
         , zIsI386                     :: Bool
         , zIsX8664                    :: Bool
+        , zIsAarch64                  :: Bool
 
         , zPrefix     :: FilePath
         , zBindir     :: FilePath
diff --git a/cabal-install/src/Distribution/Client/Compat/ExecutablePath.hs b/cabal-install/src/Distribution/Client/Compat/ExecutablePath.hs
index e805c110d60..fa989a6bd0f 100644
--- a/cabal-install/src/Distribution/Client/Compat/ExecutablePath.hs
+++ b/cabal-install/src/Distribution/Client/Compat/ExecutablePath.hs
@@ -123,7 +123,7 @@ getExecutablePath = readSymbolicLink $ "/proc/self/exe"
 
 # if defined(i386_HOST_ARCH)
 #  define WINDOWS_CCONV stdcall
-# elif defined(x86_64_HOST_ARCH)
+# elif defined(x86_64_HOST_ARCH) || defined(aarch64_HOST_ARCH)
 #  define WINDOWS_CCONV ccall
 # else
 #  error Unknown mingw32 arch
diff --git a/changelog.d/pr-10705 b/changelog.d/pr-10705
new file mode 100644
index 00000000000..e150428ca27
--- /dev/null
+++ b/changelog.d/pr-10705
@@ -0,0 +1,8 @@
+---
+synopsis: 'Add support for Windows Aarch64'
+packages: [Cabal, cabal-install]
+prs: 10705
+---
+
+Adds to preprocessor branches the option to support `aarch64_HOST_ARCH` platform on Windows Aarch64 target.
+`ccall` convention is used at Aarch64, same as for `x86_64_HOST_ARCH`. Introduce `zIsAarch64` to make paths generation support Windows Aarch64 target.