compiler: use new defer stack for inlined functions, fix #2281

Inlined functions shouldn't care about outer scope defer statements, they
can't.

pkg/compiler/defer_test.go

@@ -50,6 +50,24 @@ func TestDefer(t *testing.T) {
 		func f() { a += 2 }`
 		eval(t, src, big.NewInt(10))
 	})
+	t.Run("DeferAfterInterop", func(t *testing.T) {
+		src := `package main
+
+		import (
+			"github.com/nspcc-dev/neo-go/pkg/interop/storage"
+		)
+
+		func Main() {
+			defer func() {
+			}()
+			storage.GetContext()
+		}`
+		vm := vmAndCompile(t, src)
+		err := vm.Run()
+		require.NoError(t, err)
+		require.Equal(t, 0, vm.Estack().Len(), "stack contains unexpected items")
+	})
+
 	t.Run("MultipleDefers", func(t *testing.T) {
 		src := `package main
 		var a int

pkg/compiler/inline.go

@@ -99,6 +99,8 @@ func (c *codegen) inlineCall(f *funcScope, n *ast.CallExpr) {
 
 	c.pkgInfoInline = append(c.pkgInfoInline, pkg)
 	oldMap := c.importMap
+	oldDefers := c.scope.deferStack
+	c.scope.deferStack = nil
 	c.fillImportMap(f.file, pkg.Pkg)
 	ast.Inspect(f.decl, c.scope.analyzeVoidCalls)
 	ast.Walk(c, f.decl.Body)
@@ -107,6 +109,8 @@ func (c *codegen) inlineCall(f *funcScope, n *ast.CallExpr) {
 			emit.Opcodes(c.prog.BinWriter, opcode.DROP)
 		}
 	}
+	c.processDefers()
+	c.scope.deferStack = oldDefers
 	c.importMap = oldMap
 	c.pkgInfoInline = c.pkgInfoInline[:len(c.pkgInfoInline)-1]
 }