vcpkg_configure_make: Support macOS cross-compile (#15659)

* vcpkg_configure_make: Support macOS cross-compile

* Move compiler flags logic to get_cmake_vars

* Better match the arch behavior of config.guess

* Apply suggestions from code review

Co-authored-by: Billy O'Neal <bion@microsoft.com>

Co-authored-by: Billy O'Neal <bion@microsoft.com>

2 files changed, 67 insertions, 8 deletions

diff --git a/scripts/cmake/vcpkg_configure_make.cmake b/scripts/cmake/vcpkg_configure_make.cmake
index 122281f42..c30de38bd 100644
--- a/scripts/cmake/vcpkg_configure_make.cmake
+++ b/scripts/cmake/vcpkg_configure_make.cmake
@@ -139,6 +139,26 @@ macro(_vcpkg_determine_autotools_target_cpu out_var)
     endif()

 endmacro()

 

+macro(_vcpkg_determine_autotools_host_arch_mac out_var)

+    set(${out_var} "${VCPKG_DETECTED_CMAKE_HOST_SYSTEM_PROCESSOR}")

+endmacro()

+

+macro(_vcpkg_determine_autotools_target_arch_mac out_var)

+    list(LENGTH VCPKG_OSX_ARCHITECTURES _num_osx_archs)

+    if(_num_osx_archs GREATER_EQUAL 2)

+        set(${out_var} "universal")

+    else()

+        # Better match the arch behavior of config.guess

+        # See: https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess;hb=HEAD

+        if(VCPKG_OSX_ARCHITECTURES MATCHES "^(ARM|arm)64$")

+            set(${out_var} "aarch64")

+        else()

+            set(${out_var} "${VCPKG_OSX_ARCHITECTURES}")

+        endif()

+    endif()

+    unset(_num_osx_archs)

+endmacro()

+

 macro(_vcpkg_backup_env_variable envvar)

     if(DEFINED ENV{${envvar}})

         set(${envvar}_BACKUP "$ENV{${envvar}}")

@@ -407,6 +427,25 @@ function(vcpkg_configure_make)
         set(prefix_var "\${prefix}")

     endif()

 

+    # macOS - cross-compiling support

+    if(VCPKG_TARGET_IS_OSX)

+        if (_csc_AUTOCONFIG AND NOT _csc_BUILD_TRIPLET OR _csc_DETERMINE_BUILD_TRIPLET)

+            _vcpkg_determine_autotools_host_arch_mac(BUILD_ARCH) # machine you are building on => --build=

+            _vcpkg_determine_autotools_target_arch_mac(TARGET_ARCH)

+            # --build: the machine you are building on

+            # --host: the machine you are building for

+            # --target: the machine that CC will produce binaries for

+            # https://stackoverflow.com/questions/21990021/how-to-determine-host-value-for-configure-when-using-cross-compiler

+            # Only for ports using autotools so we can assume that they follow the common conventions for build/target/host

+            set(_csc_BUILD_TRIPLET "--build=${BUILD_ARCH}-apple-darwin")

+            if(NOT "${TARGET_ARCH}" STREQUAL "${BUILD_ARCH}") # we don't need to specify the additional flags if we build natively.

+

+                list(APPEND _csc_BUILD_TRIPLET "--host=${TARGET_ARCH}-apple-darwin") # (Host activates crosscompilation; The name given here is just the prefix of the host tools for the target)

+            endif()

+            debug_message("Using make triplet: ${_csc_BUILD_TRIPLET}")

+        endif()

+    endif()

+

     # Cleanup previous build dirs

     file(REMOVE_RECURSE "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel"

                         "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg"

@@ -671,8 +710,8 @@ function(vcpkg_configure_make)
         if (CMAKE_HOST_WIN32)

             set(command ${base_cmd} -c "${CONFIGURE_ENV} ./${RELATIVE_BUILD_PATH}/configure ${_csc_BUILD_TRIPLET} ${_csc_OPTIONS} ${_csc_OPTIONS_${_buildtype}}")

         else()

-            find_program(BASH bash REQUIRED)
-            set(command "${BASH}" "./${RELATIVE_BUILD_PATH}/configure" ${_csc_BUILD_TRIPLET} ${_csc_OPTIONS} ${_csc_OPTIONS_${_buildtype}})
+            find_program(BASH bash REQUIRED)

+            set(command "${BASH}" "./${RELATIVE_BUILD_PATH}/configure" ${_csc_BUILD_TRIPLET} ${_csc_OPTIONS} ${_csc_OPTIONS_${_buildtype}})

         endif()

         if(_csc_ADD_BIN_TO_PATH)

             set(PATH_BACKUP $ENV{PATH})

diff --git a/scripts/get_cmake_vars/CMakeLists.txt b/scripts/get_cmake_vars/CMakeLists.txt
index 45a53989b..6be594787 100644
--- a/scripts/get_cmake_vars/CMakeLists.txt
+++ b/scripts/get_cmake_vars/CMakeLists.txt
@@ -48,6 +48,12 @@ foreach(flag IN LISTS FLAGS)
 endforeach()

 list(REMOVE_DUPLICATES VCPKG_DEFAULT_FLAGS_TO_CHECK)

 

+#Language-specific flags.

+foreach(_lang IN LISTS VCPKG_LANGUAGES)

+    list(APPEND VCPKG_LANG_FLAGS CMAKE_${_lang}_FLAGS)

+endforeach()

+list(REMOVE_DUPLICATES VCPKG_LANG_FLAGS)

+

 # TODO if ever necessary: Properties to check

 

 set(VCPKG_VAR_PREFIX "VCPKG_DETECTED" CACHE STRING "Variable prefix to use for detected flags")

@@ -81,17 +87,31 @@ foreach(_env IN LISTS VCPKG_ENV_VARS_TO_CHECK)
     endif()

 endforeach()

 

+macro(_vcpkg_adjust_flags flag_var)

+    if(MSVC) # Transform MSVC /flags to -flags due to bash scripts intepreting /flag as a path.

+        string(REGEX REPLACE "(^| )/" "\\1-" ${flag_var} "${${flag_var}}")

+    endif()

+    if(CMAKE_SYSTEM_NAME MATCHES "Darwin")

+        if("${flag_var}" IN_LIST VCPKG_LANG_FLAGS)

+            # macOS - append arch and isysroot if cross-compiling

+            if(NOT "${CMAKE_OSX_ARCHITECTURES}" STREQUAL "${CMAKE_HOST_SYSTEM_PROCESSOR}")

+

+                foreach(arch IN LISTS CMAKE_OSX_ARCHITECTURES)

+                    string(APPEND ${flag_var} " -arch ${arch}")

+                endforeach()

+                string(APPEND ${flag_var} " -isysroot ${CMAKE_OSX_SYSROOT}")

+            endif()

+        endif()

+    endif()

+endmacro()

+

 foreach(flag IN LISTS VCPKG_FLAGS_TO_CHECK)

     string(STRIP "${${flag}}" ${flag}) # Strip leading and trailing whitespaces

-    if(MSVC) # Transform MSVC /flags to -flags due to bash scripts intepreting /flag as a path. 

-        string(REGEX REPLACE "(^| )/" "\\1-" ${flag} "${${flag}}")

-    endif()

+    _vcpkg_adjust_flags(${flag})

     string(APPEND OUTPUT_STRING "set(${VCPKG_VAR_PREFIX}_RAW_${flag} \" ${${flag}}\")\n")

     foreach(config IN LISTS VCPKG_CONFIGS)

         string(STRIP "${${flag}_${config}}" ${flag}_${config})

-        if(MSVC)

-            string(REGEX REPLACE "(^| )/" "\\1-" ${flag}_${config} "${${flag}_${config}}")

-        endif()

+        _vcpkg_adjust_flags(${flag}_${config})

         string(APPEND OUTPUT_STRING "set(${VCPKG_VAR_PREFIX}_RAW_${flag}_${config} \"${CMAKE_${flag}_FLAGS_${config}}\")\n")

         set(COMBINED_${flag}_${config} "${${flag}} ${${flag}_${config}}")

         string(STRIP "${COMBINED_${flag}_${config}}" COMBINED_${flag}_${config})