Add Windows ARM64 support

Currently we do not have fcontext related ASM files for Windows ARM64.
So we can use winfib context-impl only for Windows ARM64.

Fixes issue : boostorg/boost#1070
Related to PR: boostorg/boost#1077

Author: vask2108

.github/workflows/ci.yml

@@ -49,3 +49,40 @@ jobs:
         run: |
           cd ../boost-root
           ./b2 -j3 libs/$LIBRARY/test variant=debug,release
+  windows:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ windows-2022, windows-2025, windows-11-arm ]
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+          cmd /c bootstrap
+          b2 -d0 headers
+      - name: Run tests
+        shell: cmd
+        run: |
+          cd ../boost-root
+          b2 -j3 libs/%LIBRARY%/test variant=debug,release

build/Jamfile.v2

@@ -18,6 +18,7 @@ import config : requires ;
 project
     : common-requirements <library>$(boost_dependencies)
     : requirements
+      <target-os>windows,<architecture>arm,<address-model>64:<context-impl>winfib
       <target-os>windows:<define>_WIN32_WINNT=0x0601
       <target-os>linux,<toolset>gcc,<segmented-stacks>on:<cxxflags>-fsplit-stack
       <target-os>linux,<toolset>gcc,<segmented-stacks>on:<cxxflags>-DBOOST_USE_SEGMENTED_STACKS

test/Jamfile.v2

@@ -41,6 +41,10 @@ rule native-impl ( properties * )
     {
         result = <build>no ;
     }
+    else if ( <target-os>windows in $(properties) && <architecture>arm in $(properties) && <address-model>64 in $(properties) )
+    {
+        return <context-impl>winfib ;   # for windows arm64 always use winfib and skip ASM
+    }
     else if ( ! ( <target-os>windows in $(properties) ) )
     {
         result = <context-impl>ucontext ;
@@ -52,6 +56,22 @@ rule native-impl ( properties * )
     return $(result) ;
 }
 
+rule fcontext-impl ( properties * )
+{
+    # Skip on Windows ARM64
+    if ( <target-os>windows in $(properties) &&
+         <architecture>arm in $(properties) &&
+         <address-model>64 in $(properties) )
+    {
+        return <build>no ; # for windows arm64 always use winfib and skip fcontext
+    }
+    else
+    {
+        return <context-impl>fcontext ;
+    }
+}
+
+
 obj is_libstdcxx : is_libstdcxx.cpp ;
 explicit is_libstdcxx ;
 
@@ -95,7 +115,7 @@ test-suite minimal :
 
 [ run test_fiber.cpp :
     : :
-    <context-impl>fcontext
+    <conditional>@fcontext-impl
     [ requires cxx11_auto_declarations
                cxx11_constexpr
                cxx11_defaulted_functions
@@ -150,7 +170,7 @@ test-suite minimal :
 
 [ run test_callcc.cpp :
     : :
-    <context-impl>fcontext
+     <conditional>@fcontext-impl
     [ requires cxx11_auto_declarations
                cxx11_constexpr
                cxx11_defaulted_functions