From 34198fa18adce7e70101d20a351722d6cb1be93a Mon Sep 17 00:00:00 2001
From: effulgentsia <477547+effulgentsia@users.noreply.github.com>
Date: Tue, 24 Mar 2026 11:25:20 -0700
Subject: [PATCH] Add Go bindings for missing linker unknown-imports functions

---
 linker.go      | 38 ++++++++++++++++++++++++++++++++
 linker_test.go | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+)

diff --git a/linker.go b/linker.go
index a7eb8ef..1bfbfa5 100644
--- a/linker.go
+++ b/linker.go
@@ -211,6 +211,44 @@ func (l *Linker) DefineWasi() error {
 	return mkError(err)
 }
 
+// DefineUnknownImportsAsTraps defines all otherwise-missing imports of the
+// module as functions that immediately trap.
+//
+// Returns an error if the imports could not be defined.
+func (l *Linker) DefineUnknownImportsAsTraps(module *Module) error {
+	err := C.wasmtime_linker_define_unknown_imports_as_traps(
+		l.ptr(),
+		module.ptr(),
+	)
+	runtime.KeepAlive(l)
+	runtime.KeepAlive(module)
+	if err == nil {
+		return nil
+	}
+
+	return mkError(err)
+}
+
+// DefineUnknownImportsAsDefaultValues defines all otherwise-missing imports of
+// the module as values that return the default for their type.
+//
+// Returns an error if the imports could not be defined.
+func (l *Linker) DefineUnknownImportsAsDefaultValues(store Storelike, module *Module) error {
+	err := C.wasmtime_linker_define_unknown_imports_as_default_values(
+		l.ptr(),
+		store.Context(),
+		module.ptr(),
+	)
+	runtime.KeepAlive(l)
+	runtime.KeepAlive(store)
+	runtime.KeepAlive(module)
+	if err == nil {
+		return nil
+	}
+
+	return mkError(err)
+}
+
 // Instantiate instantiates a module with all imports defined in this linker.
 //
 // Returns an error if the instance's imports couldn't be satisfied, had the
diff --git a/linker_test.go b/linker_test.go
index c72ed54..01b1034 100644
--- a/linker_test.go
+++ b/linker_test.go
@@ -182,6 +182,66 @@ func TestLinkerFuncs(t *testing.T) {
 	require.Equal(t, 6, called, "expected a call")
 }
 
+func TestLinkerDefineUnknownImportsAsTraps(t *testing.T) {
+	engine := NewEngine()
+	wasm, err := Wat2Wasm(`
+	    (module
+		(import "unknown" "f" (func))
+		(func (export "run") call 0)
+	    )
+	`)
+	require.NoError(t, err)
+	module, err := NewModule(engine, wasm)
+	require.NoError(t, err)
+
+	store := NewStore(engine)
+	linker := NewLinker(engine)
+	defer linker.Close()
+	_, err = linker.Instantiate(store, module)
+	require.Error(t, err)
+
+	err = linker.DefineUnknownImportsAsTraps(module)
+	require.NoError(t, err)
+	instance, err := linker.Instantiate(store, module)
+	require.NoError(t, err)
+
+	run := instance.GetFunc(store, "run")
+	require.NotNil(t, run)
+	_, err = run.Call(store)
+	require.Error(t, err)
+}
+
+func TestLinkerDefineUnknownImportsAsDefaultValues(t *testing.T) {
+	engine := NewEngine()
+	wasm, err := Wat2Wasm(`
+	    (module
+		(import "unknown" "f" (func (result i32)))
+		(func (export "run") (result i32) call 0)
+	    )
+	`)
+	require.NoError(t, err)
+	module, err := NewModule(engine, wasm)
+	require.NoError(t, err)
+
+	store := NewStore(engine)
+	linker := NewLinker(engine)
+	defer linker.Close()
+
+	_, err = linker.Instantiate(store, module)
+	require.Error(t, err)
+
+	err = linker.DefineUnknownImportsAsDefaultValues(store, module)
+	require.NoError(t, err)
+	instance, err := linker.Instantiate(store, module)
+	require.NoError(t, err)
+
+	run := instance.GetFunc(store, "run")
+	require.NotNil(t, run)
+	result, err := run.Call(store)
+	require.NoError(t, err)
+	require.Equal(t, int32(0), result)
+}
+
 func TestPanicInHostFunctionDuringInstantiate(t *testing.T) {
 	engine := NewEngine()
 	linker := NewLinker(engine)