Go silently drops the value of a constant (non-static) field, and of every instance-field initializer: the struct is zero-valued

[matt-edmondson]

What's wrong

GoGenerator decides where a field goes from IsStatic alone:

• Coder/Languages/GoGenerator.cs ~line 580 writes package-level storage for field.IsStatic.
• ~line 732 makes a struct member of !field.IsStatic.

A FieldDeclaration with IsConstant = true and IsStatic = false therefore becomes an ordinary struct field, and its InitialValue is dropped with no note. Every other target treats a constant as belonging to the type:

Target	Output for Ratio (constant, 0.5)
C#	public static readonly double Ratio = 0.5d;
C++	static constexpr double Ratio = 0.5;
Rust (fixed in #81)	pub const Ratio: f64 = 0.5; via IsStatic || IsConstant
C	double Ratio; // constant, 0.5
Go	Ratio float64 (value lost)

Go also drops ordinary instance-field initializers without a note. Hits = 5 becomes Hits int, and the generated constructor returns Cfg{}. C at least writes // defaults to 5.

Repro

var cls = new ClassDeclaration("Cfg") { Kind = TypeDeclarationKind.Struct };
cls.Members.Add(new FieldDeclaration("Ratio", new TypeReference("double")) { IsConstant = true, InitialValue = Literal.DecimalValue(0.5) });
cls.Members.Add(new FieldDeclaration("Hits", new TypeReference("int")) { InitialValue = Literal.Number(5) });
cls.Members.Add(new FunctionDeclaration("Cfg") { Kind = FunctionKind.Constructor });
Console.WriteLine(new GoGenerator().Generate(cls));

Actual:

type Cfg struct {
	Ratio float64
	Hits  int
}
func NewCfg() Cfg { return Cfg{} }

Under go run, printing NewCfg()'s fields gives 0 0. The C# and C++ outputs give 0.5 and 5.

Suggested fix

• Change both predicates to field.IsStatic || field.IsConstant, matching RustGenerator.IsAssociatedField. Ratio then becomes a package-level const CfgRatio float64 = 0.5, the same path static fields already take.
• For instance fields with an InitialValue, set them in the generated constructor's composite literal (Cfg{Hits: 5}), or at least emit a note as the C generator does.

Acceptance criteria

• Constant fields keep their value in Go output.
• A struct with initialized instance fields constructed via NewX() reports the initial values, or the output carries an explicit note that they are not applied.

[matt-edmondson]

Triage

• Category: Bug
• Priority: High. The Go output compiles and runs but silently gives zero values where the model says 0.5 and 5. No error or note warns the caller, so wrong behaviour ships unnoticed.
• Area / suggested owner: GoGenerator field placement (~580 / ~732) and constructor composite-literal generation
• Duplicates / in progress: None found. This is the Go counterpart of the Rust fix in Rust generator turns static/const fields inside a type into per-instance struct fields and silently drops their value #81 (IsStatic || IsConstant), and a companion to JavaScript ignores FieldDeclaration.IsStatic/IsConstant: static class fields become per-instance, and a file-scope field is an undeclared assignment that throws in an ES module #104 (JavaScript ignoring IsStatic/IsConstant). No open PR references it.
• Notes: The constant half is a two-predicate change that reuses the existing static-field path. The instance-initializer half (Cfg{Hits: 5}) is larger and could ship separately, with a C-style note as the interim fallback.

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