Merge pull request #75559 from rintaro/6.0-package-cmo-beta4

[6.0][CMake] Enable package CMO only in newer compilers

Author: bnbarham

cmake/modules/SwiftCompilerCapability.cmake

@@ -21,6 +21,19 @@ macro(swift_supports_implicit_module module_name out_var)
  )
 endmacro()
 
+function(swift_get_swiftlang_version out_var)
+ execute_process(
+ COMMAND "${CMAKE_Swift_COMPILER}" -version
+ OUTPUT_VARIABLE output ERROR_VARIABLE output
+ RESULT_VARIABLE result
+ TIMEOUT 10
+ )
+
+ if(output MATCHES [[swiftlang-([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)]])
+ set("${out_var}" "${CMAKE_MATCH_1}" PARENT_SCOPE)
+ endif()
+endfunction()
+
 # Get "package cross-module-optimization" compiler arguments suitable for the compiler.
 function(swift_get_package_cmo_support out_var)
  # > 6.0 : Fixed feature.
@@ -42,8 +55,13 @@ function(swift_get_package_cmo_support out_var)
  -Xfrontend -experimental-package-bypass-resilience
  )
  if(result)
- set(${out_var} EXPERIMENTAL PARENT_SCOPE)
- return()
+ # Package CMO is implmented in Xcode 16 Beta 4 (swiftlang-6.0.0.6.8) or later.
+ # Consider it's not supported in non Xcode toolchain with "-experimental" options.
+ swift_get_swiftlang_version(swiftlang_version)
+ if(swiftlang_version AND swiftlang_version VERSION_GREATER_EQUAL 6.0.0.6)
+ set(${out_var} EXPERIMENTAL PARENT_SCOPE)
+ return()
+ endif()
  endif()
 
  # < 6.0 : Not supported.