Fix iOS sdks build on Xcode 12 (#20574)mono-6.12.0.111
commit124f1157141b323b6de883b45021170f1fe70539
authormonojenkins <jo.shields+jenkins@xamarin.com>
Fri, 13 Nov 2020 13:29:43 +0000 (13 08:29 -0500)
committerGitHub <noreply@github.com>
Fri, 13 Nov 2020 13:29:43 +0000 (13 14:29 +0100)
tree8f8b917bc836914523c93aa59cbc9011c183d630
parentdfbfe5eed1992905b0dac80a8dc7d6f1f9647735
Fix iOS sdks build on Xcode 12 (#20574)

The new Xcode introduced functions like preadv/pwritev in the SDK that get erraneously detected by autoconf even though we can't use them.
Disable these functions and also add a check for Xcode version to workaround https://github.com/mono/mono/issues/19393.

Co-authored-by: Alexander Köplinger <alex.koeplinger@outlook.com>
sdks/builds/ios.mk
sdks/builds/mac.mk
sdks/versions.mk