Highlights of the release

• Support records in JavaParsers #16762
• Port JVM backend refactor from Scala 2 #15322

Other changes and fixes

Backend

• Disallow mixins where super calls bind to vals #16908
• Fix #15107: Avoid re-emitting a LineNumber after only LabelNodes. #16813

Coverage

• Fix #17042: Preserve the shape of secondary ctors in instrumentCoverage. #17111

Default parameters

• Dupe fix when finding default arg getters #17058

Documentation

• Fix: ensure syntax blocks for ebnf are marked as such #16837

Erasure

• Handle @companionClass and @companionMethod meta-annotations #17091

Extension Methods

• Support extension methods imported from different objects #17050

GADTs

• Fix tuple member selection so it works with GADT healing #16766
• Fix upper bound constraints, that are higher-kinded #16744
• Split out immutable GadtConstraint #16602

Implicits

• Improve subtyping check for not yet eta-expanded higher kinded types #17139
• Harden tpd.Apply/TypeApply in case of errors #16887
• Try to be more subtle when inferring type parameters of class parents #16896
• Include P in the implicit scope of P.this.type #17088

Incremental Compilation

• Fix under-compilation when the method type in a SAM changes #16996

Infrastructure

• Set reference version to 3.3.0-RC6 #17504
• Fix #17119: Download Coursier from GitHub directly #17141

Inline

• Remove NamedArg from inlined arguments #17228
• Don't generate a Select for a TermRef with NoPrefix #16754
• Prepare bodies of inline forwarders eagerly #16757
• Do not remove inline method implementations until PruneErasedDefs #17408

Java Interop

• ClassfileParser: allow missing param names (for JDK 21) #17536

Linting

• Improve -Wunused: locals, privates with unset vars warning #16639 #17160
• Fix wunused false positive when deriving alias type #17157
• Port -Wnonunit-statement setting for dotty #16936

Match Types

• Normalize match type usage during implicit lookup #17457
• Fix #13757: Explicitly disallow higher-kinded scrutinees of match types. #17322
• Fix match type reduction with wildcard type arguments #17065
• Fix check whether classtag can be generated for match types #16708

Parser

• Allow lines starting with . to fall outside previous indentation widths #17056

Pattern Matching

• Fix #11541: Specialize ClassTag[T] in exhaustivity check #17385
• Check outer class prefixes in type projections when pattern matching #17136
• Make unchecked cases non-@unchecked and non-unreachable #16958
• Fix #16899: Better handle X instanceOf P where X is T1 | T2 #17382

Pickling

• ClassfileParser: Avoid cycle when accessing companion in inner class lookup #16882

Polyfunctions

• Fix type aliases in beta-reduction of polyfunctions #17054

Quotes

• Register paramProxy and thisProxy in Quote type #17541
• Only check newVal/newMethod privateWithin on -Xcheck-macros #17437
• Unencode quote and splice trees #17342
• Correctly type Expr.ofTupleFromSeq for arity > 22 #17261
• Use TermRef to distinguish distinct Type[T] instances #17205
• Check level consistency of SingletonTypeTree as a type #17209
• Fix splice type variable pattern detection #17048
• Avoid creation of @SplicedType quote local refrences #17051
• Dealias type references when healing types in quotes #17049
• Replace quoted type variables in signature of HOAS pattern result #16951
• Beta-reduce directly applied PolymorphicFunction #16623
• Use Object.toString for quoted.{Expr, Type} #16663
• Fix Splicer.isEscapedVariable #16838
• Fix references to class members defined in quotes #17107
• Handle pickled forward references in pickled expressions #16855
• Fix #16615 - crashes of path dependent types in spliced Type.of #16773
• Disallow local term references in staged types #16362
• Refactor level checking / type healing logic #17082
• Dealias quoted types when staging #17059
• Fix quotes with references to path dependent types #17081
• Make arguments order in quote hole deterministic #17405
• Only transform the body of the quote with QuoteTransformer #17451
• Place staged type captures in Quote AST #17424
• Add SplicePattern AST to parse and type quote pattern splices #17396

Reflection

• -Xcheck-macros: add hint when a symbol in created twice #16733
• Assert that symbols created using reflect API have correct privateWithin symbols #17352
• Fix reflect.LambdaType type test #16972
• Improve New/Select -Ycheck message #16746
• Improve error message for CyclicReference in macros #16749
• Add reflect defn.FunctionClass overloads #16849

REPL

• Always load REPL classes in macros including the output directory #16866

Reporting

• Improve missing argument list error #17126
• Improve implicit parameter error message with aliases #17125
• Improve "constructor proxy shadows outer" handling #17154
• Clarify ambiguous reference error message #16137
• Hint about forbidden combination of implicit values and conversions #16735
• Attach explanation message to diagnostic message #16787
• Propagate implicit search errors from implicit macros #16840
• Detail UnapplyInvalidReturnType error message #17167
• Add way to debug -Xcheck-macros tree checking #16973
• Enrich and finesse compiler crash reporting #17031
• Allow @implicitNotFound messages as explanations #16893
• Include top-level symbols from same file in outer ambiguity error #17033
• Do not issue deprecation warnings when declaring deprecated case classes #17165

Scala-JS

• Fix #17344: Make implicit references to this above dynamic imports explicit. #17357
• Fix #12621: Better error message for JS trait ctor param. #16811
• Fix #16801: Handle Closure's of s.r.FunctionXXL. #16809
• Fix #17549: Unify how Memoize and Constructors decide what fields need storing. #17560

Scaladoc

• Feat: Add a blog configuration with yaml #17214
• Don't render the "$" for module #17302
• Fix: Add scrollbar to the sidebar #17203
• Scaladoc: fix crash when processing extends call #17260
• Fix: Modify the CSS so that the logo of the generated documentation is adaptive #17172
• Fix: Remove the duplicate parameter when generating the scaladoc. #17097
• Fix: padding top in mobile version #17019
• Fix: tap target of the menu in Mobile version #17018
• Scaladoc: Fix expand icon not changing on anchor link #17053
• Scaladoc: fix inkuire generation for PolyTypes #17129
• Re port scroll bar #17463
• Handle empty files and truncated YAML front matter #17527

SemanticDB

• Make sure symbol exists before calling owner #16860
• Support LambdaType (convert from HKTypeLambda) #16056

Specification

• Apply class-shadowing.md to the Spec #16839
• Adding base for future Spec into the compiler repo #16825

Standard Library

• Optimization: avoid NotGiven allocations #17090

Tooling

• Disable ExtractSemanticDB phase when writing to output directory defined as JAR. #16790
• Print owner of bind symbol with -Yprint-debug-owners #16854
• Small fixes to allow using Metals with scaladoc with sbt #16816

Transform

• Move CrossVersionChecks before FirstTransform #17301
• Fix needsOuterIfReferenced #17159
• Drop incorrect super accessor in trait subclass #17062
• Generate toString only for synthetic companions of case classes #16890
• Check trait constructor for accessibility even if not called at Typer #17094
• Fix #17435: A simpler fix #17436

Typer

• Preserve type bounds for inlined definitions in posttyper #17190
• Change logic to find members of recursive types #17386
• Recognize named arguments in isFunctionWithUnknownParamType #17161
• Better comparisons for type projections #17092
• Allow selectDynamic and applyDynamic to be extension methods #17106
• Fix use of accessibleFrom when finding default arg getters #16977
• Map class literal constant types #16988
• Always use adapted type in withDenotation #16901
• Restrict captureWildcards to only be used if needed #16799
• Don't capture wildcards if in closure or by-name #16732
• Infer: Don't minimise to Nothing if there's an upper bound #16786
• Perform Matchable check only if type test is needed #16824
• Don't eta expand unary varargs methods #16892
• Fix beta-reduction with Nothing and null args #16938
• Generate kind-correct wildcards when selecting from a wildcard #17025
• Fix #16405 ctd - wildcards prematurely resolving to Nothing #16764
• Test: add regression test for #7790 #17473
• Properly handle AnyVals as refinement members of Selectables #16286

Contributors

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

According to git shortlog -sn --no-merges 3.3.0..3.3.1 these are:

   152	Nicolas Stucki
    73	Martin Odersky
    54	Dale Wijnand
    51	Szymon Rodziewicz
    49	Quentin Bernet
    38	Chris Kipp
    31	Paweł Marks
    19	David Hua
    18	Lucas
    18	ysthakur
    15	Fengyun Liu
    14	Guillaume Martres
    14	Jamie Thompson
    11	Sébastien Doeraene
     9	Timothée Andres
     8	Kacper Korban
     7	Matt Bovel
     7	Som Snytt
     6	Julien Richard-Foy
     6	Lucas Leblanc
     5	Michał Pałka
     4	Anatolii Kmetiuk
     4	Guillaume Raffin
     4	Jan Chyb
     4	Paul Coral
     4	Wojciech Mazur
     4	Yichen Xu
     3	Decel
     2	Adrien Piquerez
     2	Arman Bilge
     2	Carl
     2	Florian3k
     2	Kenji Yoshida
     2	Michael Pilquist
     2	Natsu Kagami
     2	Seth Tisue
     2	Tomasz Godzik
     2	Vasil Vasilev
     2	Yadu Krishnan
     1	Bersier
     1	Flavio Brasil
     1	Jan-Pieter van den Heuvel
     1	Lukas Rytz
     1	Miles Yucht
     1	Mohammad Yousuf Minhaj Zia
     1	Ondra Pelech
     1	Philippus
     1	Rikito Taniguchi
     1	Simon R
     1	brandonspark
     1	github-actions[bot]
     1	liang3zy22
     1	s.bazarsadaev
     1	Łukasz Wroński