Backported fixes

• Fix a bundle of patmat issues #21000
• Fixed false positive unreachable local object #21532
• Reimplement support for type aliases in SAM types #18317
• Allow SAM types to contain match alias refinements #20092
• Allow SAM types to contain multiple refinements #20172

Contributors

Thank you to all the contributors who made this release possible 🎉

According to git shortlog -sn --no-merges 3.3.4-RC1..3.3.4-RC2 these are:

    11  Dale Wijnand
     7  Wojciech Mazur
     1  Guillaume Martres