message: darwin: pass mlinker-version so that clang enables new features
  Without this clang fails to add any newly-added linker features.
  Removing this in was likely a
  regression.
  See
  for more discussion.
diff: @@ -2,9 +2,11 @@ OSX_MIN_VERSION=10.12
  OSX_SDK_VERSION=10.15.1
  XCODE_VERSION=11.3.1
  XCODE_BUILD_ID=11C505
  +LD64_VERSION=530
  +
  OSX_SDK=$(SDK_PATH)/Xcode-$(XCODE_VERSION)-$(XCODE_BUILD_ID)-extracted-SDK-with-libcxx-headers
  -darwin_CC=clang -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK)
  -darwin_CXX=clang++ -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -stdlib=libc++
  +darwin_CC=clang -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -mlinker-version=$(LD64_VERSION)
  +darwin_CXX=clang++ -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -stdlib=libc++ -mlinker-version=$(LD64_VERSION)
  darwin_CFLAGS=-pipe
  darwin_CXXFLAGS=$(darwin_CFLAGS)
  