This version of Xcode requires macOS 11.0 or later.
New commits in xamarin/maccore:
* xamarin/maccore@de616ca53e [mlaunch] Fix dependencies for Xcode 12.5 beta 1 (#2387)
* xamarin/maccore@e93375583c [Actions] Fix rebase trigger.
* xamarin/maccore@0dfeb85ff6 [CI][VSTS] Add information when the external tool fails. (#2377)
* xamarin/maccore@87e165fdbb Remove Vincent as a code owner 😞 (#2368)
* xamarin/maccore@55a700bb5b [build] Add /restore to Xamarin.Analysis build (#2366)
* xamarin/maccore@2d9f8a9685 Bump to xamarin/xamarin-analysis@95245313 (#2362)
Diff: 428964bf32..de616ca53e
* Bump system mono to the latest available 2020-02 package. (#10402)
This makes xamarin-macios build on Apple Silicon, and also seems to get an
updated csc that fixes a problem with nullability warnings/errors.
* [tests] Fix mmp-regression build
```
10:59:46.5383210 Making all in /Users/builder/azdo/_work/1/s/xamarin-macios/tests/mmp-regression
10:59:46.5392610 TargetFrameworkFallbackSearchPaths=/Users/builder/azdo/_work/1/s/xamarin-macios/_mac-build/Library/Frameworks/Mono.framework/External/xbuild-frameworks MSBuildExtensionsPathFallbackPathsOverride=/Users/builder/azdo/_work/1/s/xamarin-macios/_mac-build/Library/Frameworks/Mono.framework/External/xbuild make all
10:59:46.6208220 /Applications/Xcode_12.5.0-beta.app/Contents/Developer/usr/bin/make clean
10:59:46.6956100 /Applications/Xcode_12.5.0-beta.app/Contents/Developer/usr/bin/make build
10:59:46.7422460 GEN dylib/libTest.dylib
10:59:46.8094820 ld: library not found for -lSystem
10:59:46.8097590 clang: error: linker command failed with exit code 1 (use -v to see invocation)
10:59:46.8110310 make[2]: *** [dylib/libTest.dylib] Error 1
10:59:46.8112570 make[1]: *** [run] Error 2
10:59:47.0030120 Process make exited with 2
```
This happens on BigSur as it does not find the default location anymore...
* [tests] Do not test GKLeaderboardViewController on BigSur
The issue is the OS version, not the Xcode version. Update check
to skip that test on macOS 11+
* [tests] Fix MSBuild tests / integration
The test cannot work on BigSur since while you can `dlopen` the library
you can open `fopen` it as a file (and can't embed it for the test).
```
12:31:23.9407820 CSC : error CS1566: Error reading resource 'libz.dylib' -- 'Could not find file "/usr/lib/libz.dylib"' [/Users/builder/azdo/_work/1/s/xamarin-macios/tests/msbuild/Xamarin.MacDev.Tests/bin/Debug/net472/tmp-test-dir/msbuild-tests201/XM45Binding.csproj]
12:31:23.9407900 Done Building Project "/Users/builder/azdo/_work/1/s/xamarin-macios/tests/msbuild/Xamarin.MacDev.Tests/bin/Debug/net472/tmp-test-dir/msbuild-tests201/XM45Binding.csproj" (default targets) -- FAILED.
```
* [tests] Fix MTouch tests failures
* `nm` changed it's output and test was updated
* `clang` linking has a much higher limit for it's command-line length
At least it does not seem to be OS specific since both 10.15 and 11.0
returns the same maximum
```
$ getconf ARG_MAX
1048576
```
32bce7fc1f