Fix compiler-rt build on macOS without XCode

[arichardson]

Summary

Starting with 8a5bfbe6db2824642bf9a1d27a24c5b6132b244f (D68292) this file
unconditionally uses xcodebuild to get the SDK version. On my system this
always fails with
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance

[yln]

@delcypher: would xcrun --sdk ${sdk_name} --show-sdk-version work in all cases? If yes, we could use it instead of xcodebuild.

LGTM otherwise.

compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake

10

Would this function benefit from a similar change?

71

Nitpick: indent not consistent with other occurences.

[delcypher]

compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake

10

Yes we should but perhaps as a separate patch?

52

I would just replace all the xcodebuild commands in find_darwin_sdk_version with xcrun --sdk ${sdk_name} --show-sdk-version.

[delcypher]

In D69610#1727552, @yln wrote:

@delcypher: would xcrun --sdk ${sdk_name} --show-sdk-version work in all cases? If yes, we could use it instead of xcodebuild.

LGTM otherwise.

@yln I think so.

[arichardson]

Use xcrun instead of xcodebuild

[arichardson]

As I don't have XCode installed, it would be great if someone who does can confirm that this still works as expected.

[arichardson]

compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake

10

See D69659

[yln]

Applied it locally, ninja check-asan still works after rm -rf projects/compiler-rt. Thanks Alexander!

[delcypher]

LGTM. Thanks for the patch.

compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake

 include(CMakeParseArguments)
 include(CompilerRTUtils)
 include(BuiltinTests)
 
 set(CMAKE_LIPO "lipo" CACHE PATH "path to the lipo tool")
 
 # On OS X SDKs can be installed anywhere on the base system and xcode-select can
 # set the default Xcode to use. This function finds the SDKs that are present in
 # the current Xcode.
 function(find_darwin_sdk_dir var sdk_name)
   set(DARWIN_${sdk_name}_CACHED_SYSROOT "" CACHE STRING "Darwin SDK path for SDK ${sdk_name}.")
   set(DARWIN_PREFER_PUBLIC_SDK OFF CACHE BOOL "Prefer Darwin public SDK, even when an internal SDK is present.")
 
   if(DARWIN_${sdk_name}_CACHED_SYSROOT)
     set(${var} ${DARWIN_${sdk_name}_CACHED_SYSROOT} PARENT_SCOPE)
     return()
   endif()
   if(NOT DARWIN_PREFER_PUBLIC_SDK)

 
 function(find_darwin_sdk_version var sdk_name)
   # We deliberately don't cache the result here because
   # CMake's caching causes too many problems.
   set(result_process 1)
   if(NOT DARWIN_PREFER_PUBLIC_SDK)
     # Let's first try the internal SDK, otherwise use the public SDK.
     execute_process(
-      COMMAND xcodebuild -version -sdk ${sdk_name}.internal SDKVersion
+      COMMAND xcrun --sdk ${sdk_name}.internal --show-sdk-version
       RESULT_VARIABLE result_process
       OUTPUT_VARIABLE var_internal
       OUTPUT_STRIP_TRAILING_WHITESPACE
       ERROR_FILE /dev/null
     )
   endif()
   if((NOT ${result_process} EQUAL 0) OR "" STREQUAL "${var_internal}")
     execute_process(
-      COMMAND xcodebuild -version -sdk ${sdk_name} SDKVersion
+      COMMAND xcrun --sdk ${sdk_name} --show-sdk-version
       RESULT_VARIABLE result_process
       OUTPUT_VARIABLE var_internal
       OUTPUT_STRIP_TRAILING_WHITESPACE
       ERROR_FILE /dev/null
     )
   endif()
   if(NOT result_process EQUAL 0)
     message(FATAL_ERROR
       "Failed to determine SDK version for \"${sdk_name}\" SDK")
   endif()
   # Check reported version looks sane.
   if (NOT "${var_internal}" MATCHES "^[0-9]+\\.[0-9]+(\\.[0-9]+)?$")
     message(FATAL_ERROR
       "Reported SDK version \"${var_internal}\" does not look like a version")
   endif()
   set(${var} ${var_internal} PARENT_SCOPE)
 endfunction()