A field, auto-property, or event initializer is written once at its
declaration, but in IL it runs in every instance constructor that does not
chain to this(...) (and static initializers run in the static constructor).
The decompiler lifts the initializer from a single constructor, so its
breakpoint was emitted only there and the other constructors had none.
Two causes are addressed:
- The lift discarded the initializer's copies in the other constructors.
They are now kept on MemberInitializerInOtherConstructorsAnnotation and
replayed by SequencePointBuilder, mapping the same source location onto
each constructor's IL.
- PortablePdbWriter only emitted methods that DebugInfoGenerator discovered
through declaration syntax, so a constructor whose declaration is omitted
from the output (implicit default ctor, implicit static ctor, primary
ctor) dropped its generated points. Those functions are now emitted by
walking the sequence-point map directly.
PdbGen fixtures cover single, multiple, this()-chained, implicit, static,
primary-constructor, and field-like event initializers, pinning the
reconstructed breakpoint map against the C# compiler's.
Assisted-by: Claude:claude-opus-4-8:Claude Code
Turn on #nullable enable across the AST consumer layer: the output visitor, the
IL-to-C# builders (statement, call and expression builders, CSharpDecompiler,
TypeSystemAstBuilder), the translation-result wrappers, the sequence-point and
required-namespace collectors, and the annotation helpers. Optional inputs,
fields and returns are typed nullable, detector out-parameters use
[NotNullWhen(true)], and structurally-guaranteed dereferences use the
null-forgiving operator. A few public parameters that already tolerate null are
widened to match their downstream callers. The annotations emit no IL, so the
Pretty suite stays byte-identical.
Assisted-by: Claude:claude-opus-4-8:Claude Code
With every optional slot nullable, the null-object pattern is dead. Generated
non-nullable getters return the backing field directly, which surfaced a last
tier of slots the decompiler legitimately leaves empty (omitted range operands,
an implicitly-typed array creation, unnamed parameters, an unbound generic
argument, and others) and flips them to nullable too. The machinery is then
removed entirely: the per-node null classes, the .Null statics and
VisitNullNode, AstNode.IsNull, the role null object, and Identifier.Null.
AcceptVisitor becomes unconditionally generated, and consumers move from
.IsNull to is null and from unconditional visits to ?.AcceptVisitor.
Assisted-by: Claude:claude-opus-4-8:Claude Code
Optional single-child slots return T? with a real null instead of a role
null-object, taking the C# grammar as the oracle for which slots are optional.
The generator emits the property type as T? and matches it with MatchOptional,
and consumers move from .IsNull to is null / ?.. This covers the optional
statement, member, try-catch, creation-initializer and pattern slots and the
optional NameSlot tokens. A few slots the grammar marks required but the
decompiler legitimately leaves empty (the implicit-element-access target, an
implicitly-typed lambda parameter's type) are flipped to nullable as well.
Assisted-by: Claude:claude-opus-4-8:Claude Code
Source locations were virtual, computed by recursing to the first and last
child, whose leftmost and rightmost leaves are token nodes; sequence-point
coordinates likewise came from reconstructed token nodes. Store locations as
fields assigned while printing, and derive sequence-point coordinates from the
surrounding real nodes plus the decompiler's fixed formatting, so neither
depends on token children. The using/foreach await modifier becomes a plain
bool field. Characterization gates lock the emitted locations and PDB
coordinates, which are unchanged.
Assisted-by: Claude:claude-opus-4-8:Claude Code
or implicit sequence point without creating overlapping sequence points.
If such a location cannot be found do, nothing. Fill in the
gaps with hidden sequence points.
Also emit a sequence point for
the prolog to account for seqeunce point there emitted by the C#
compiler. Without this, the debugger can stop there on a step in
using the original pdb, then decompile resulting in a no-code at this
location failure.
Siegfried Pammer
nikitalita
Peter Crabtree
Kirill Osenkov
dotnet format
Jackson Davis
Daniel Grunwald