diff --git a/internal/cabi/_testdata/arch/amd64/empty.ll b/internal/cabi/_testdata/arch/amd64/empty.ll
new file mode 100644
index 00000000..12759287
--- /dev/null
+++ b/internal/cabi/_testdata/arch/amd64/empty.ll
@@ -0,0 +1,54 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "amd64-unknown-linux-gnu"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local void @demo1() #0 {
+  %1 = alloca %struct.empty, align 1
+  %2 = alloca %struct.empty, align 1
+  %3 = bitcast %struct.empty* %1 to i8*
+  %4 = bitcast %struct.empty* %2 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 %3, i8* align 1 %4, i64 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i64, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo2(i32 noundef %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo3(i32 noundef %0, i32 noundef %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone uwtable "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4}
+!llvm.ident = !{!5}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 7, !"PIC Level", i32 2}
+!2 = !{i32 7, !"PIE Level", i32 2}
+!3 = !{i32 7, !"uwtable", i32 2}
+!4 = !{i32 7, !"frame-pointer", i32 2}
+!5 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/arch/arm64/empty.ll b/internal/cabi/_testdata/arch/arm64/empty.ll
new file mode 100644
index 00000000..7917b49c
--- /dev/null
+++ b/internal/cabi/_testdata/arch/arm64/empty.ll
@@ -0,0 +1,58 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64-unknown-linux-gnu"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local void @demo1() #0 {
+  %1 = alloca %struct.empty, align 1
+  %2 = alloca %struct.empty, align 1
+  %3 = bitcast %struct.empty* %1 to i8*
+  %4 = bitcast %struct.empty* %2 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 %3, i8* align 1 %4, i64 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i64, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo2(i32 noundef %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo3(i32 noundef %0, i32 noundef %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone uwtable "frame-pointer"="non-leaf" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic" "target-features"="+neon,+v8a" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4, !5, !6, !7, !8}
+!llvm.ident = !{!9}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 8, !"branch-target-enforcement", i32 0}
+!2 = !{i32 8, !"sign-return-address", i32 0}
+!3 = !{i32 8, !"sign-return-address-all", i32 0}
+!4 = !{i32 8, !"sign-return-address-with-bkey", i32 0}
+!5 = !{i32 7, !"PIC Level", i32 2}
+!6 = !{i32 7, !"PIE Level", i32 2}
+!7 = !{i32 7, !"uwtable", i32 2}
+!8 = !{i32 7, !"frame-pointer", i32 1}
+!9 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/arch/armv6/empty.ll b/internal/cabi/_testdata/arch/armv6/empty.ll
new file mode 100644
index 00000000..db1d6eab
--- /dev/null
+++ b/internal/cabi/_testdata/arch/armv6/empty.ll
@@ -0,0 +1,58 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
+target triple = "armv6kz-unknown-linux-gnueabihf"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone
+define dso_local void @demo1() #0 {
+  %1 = alloca %struct.empty, align 1
+  %2 = alloca %struct.empty, align 1
+  %3 = bitcast %struct.empty* %1 to i8*
+  %4 = bitcast %struct.empty* %2 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 1 %3, i8* align 1 %4, i32 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i32, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone
+define dso_local i32 @demo2(i32 noundef %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone
+define dso_local i32 @demo3(i32 noundef %0, i32 noundef %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="arm1176jzf-s" "target-features"="+armv6kz,+dsp,+fp64,+strict-align,+vfp2,+vfp2sp,-aes,-d32,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fullfp16,-neon,-sha2,-thumb-mode,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4, !5, !6, !7, !8}
+!llvm.ident = !{!9}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 1, !"min_enum_size", i32 4}
+!2 = !{i32 8, !"branch-target-enforcement", i32 0}
+!3 = !{i32 8, !"sign-return-address", i32 0}
+!4 = !{i32 8, !"sign-return-address-all", i32 0}
+!5 = !{i32 8, !"sign-return-address-with-bkey", i32 0}
+!6 = !{i32 7, !"PIC Level", i32 2}
+!7 = !{i32 7, !"PIE Level", i32 2}
+!8 = !{i32 7, !"frame-pointer", i32 2}
+!9 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/arch/i386/empty.ll b/internal/cabi/_testdata/arch/i386/empty.ll
new file mode 100644
index 00000000..118fc29a
--- /dev/null
+++ b/internal/cabi/_testdata/arch/i386/empty.ll
@@ -0,0 +1,57 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
+target triple = "i386-unknown-linux-gnu"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local void @demo1(%struct.empty* noalias sret(%struct.empty) align 1 %0) #0 {
+  %2 = alloca i8*, align 4
+  %3 = alloca %struct.empty, align 1
+  %4 = bitcast %struct.empty* %0 to i8*
+  store i8* %4, i8** %2, align 4
+  %5 = bitcast %struct.empty* %0 to i8*
+  %6 = bitcast %struct.empty* %3 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 1 %5, i8* align 1 %6, i32 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i32, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo2(i32 noundef %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @demo3(i32 noundef %0, i32 noundef %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone uwtable "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="pentium4" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = !{i32 1, !"NumRegisterParameters", i32 0}
+!1 = !{i32 1, !"wchar_size", i32 4}
+!2 = !{i32 7, !"PIC Level", i32 2}
+!3 = !{i32 7, !"PIE Level", i32 2}
+!4 = !{i32 7, !"uwtable", i32 2}
+!5 = !{i32 7, !"frame-pointer", i32 2}
+!6 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/arch/riscv64/empty.ll b/internal/cabi/_testdata/arch/riscv64/empty.ll
new file mode 100644
index 00000000..6772b3d8
--- /dev/null
+++ b/internal/cabi/_testdata/arch/riscv64/empty.ll
@@ -0,0 +1,53 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n64-S128"
+target triple = "riscv64-unknown-unknown-elf"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone
+define dso_local void @demo1() #0 {
+  %1 = alloca %struct.empty, align 1
+  %2 = alloca %struct.empty, align 1
+  %3 = bitcast %struct.empty* %1 to i8*
+  %4 = bitcast %struct.empty* %2 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 %3, i8* align 1 %4, i64 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i64, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone
+define dso_local signext i32 @demo2(i32 noundef signext %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone
+define dso_local signext i32 @demo3(i32 noundef signext %0, i32 noundef signext %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-features"="+64bit,+a,+c,+m,+relax,-save-restore" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0, !1, !2, !3}
+!llvm.ident = !{!4}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 1, !"target-abi", !"lp64"}
+!2 = !{i32 7, !"frame-pointer", i32 2}
+!3 = !{i32 1, !"SmallDataLimit", i32 8}
+!4 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/arch/wasm32/empty.ll b/internal/cabi/_testdata/arch/wasm32/empty.ll
new file mode 100644
index 00000000..8e6de221
--- /dev/null
+++ b/internal/cabi/_testdata/arch/wasm32/empty.ll
@@ -0,0 +1,50 @@
+; ModuleID = '../../wrap/empty.c'
+source_filename = "../../wrap/empty.c"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-f128:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-emscripten"
+
+%struct.empty = type {}
+
+; Function Attrs: noinline nounwind optnone
+define hidden void @demo1() #0 {
+  %1 = alloca %struct.empty, align 1
+  %2 = alloca %struct.empty, align 1
+  %3 = bitcast %struct.empty* %1 to i8*
+  %4 = bitcast %struct.empty* %2 to i8*
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 1 %3, i8* align 1 %4, i32 0, i1 false)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nounwind willreturn
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i32, i1 immarg) #1
+
+; Function Attrs: noinline nounwind optnone
+define hidden i32 @demo2(i32 noundef %0) #0 {
+  %2 = alloca %struct.empty, align 1
+  %3 = alloca i32, align 4
+  store i32 %0, i32* %3, align 4
+  %4 = load i32, i32* %3, align 4
+  ret i32 %4
+}
+
+; Function Attrs: noinline nounwind optnone
+define hidden i32 @demo3(i32 noundef %0, i32 noundef %1) #0 {
+  %3 = alloca %struct.empty, align 1
+  %4 = alloca i32, align 4
+  %5 = alloca i32, align 4
+  store i32 %0, i32* %4, align 4
+  store i32 %1, i32* %5, align 4
+  %6 = load i32, i32* %4, align 4
+  %7 = load i32, i32* %5, align 4
+  %8 = add nsw i32 %6, %7
+  ret i32 %8
+}
+
+attributes #0 = { noinline nounwind optnone "frame-pointer"="none" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="generic" }
+attributes #1 = { argmemonly nofree nounwind willreturn }
+
+!llvm.module.flags = !{!0}
+!llvm.ident = !{!1}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}
diff --git a/internal/cabi/_testdata/demo/empty.go b/internal/cabi/_testdata/demo/empty.go
new file mode 100644
index 00000000..76c56335
--- /dev/null
+++ b/internal/cabi/_testdata/demo/empty.go
@@ -0,0 +1,57 @@
+package main
+
+import "unsafe"
+
+const (
+	LLGoFiles = "../wrap/empty.c"
+)
+
+//go:linkname printf C.printf
+func printf(format *byte, __llgo_va_list ...any) int32
+
+func assert(info string, b bool) {
+	if !b {
+		printf(unsafe.StringData("Assertion failed: %s\n\000"), unsafe.StringData(info))
+	}
+}
+
+func main() {}
+
+type empty struct {
+}
+
+//go:linkname cdemo1 C.demo1
+func cdemo1(empty) empty
+
+func demo1(a empty) empty {
+	return a
+}
+
+func init() {
+	assert("cdemo1", cdemo1(empty{}) == empty{})
+	assert("demo1", demo1(empty{}) == empty{})
+}
+
+//go:linkname cdemo2 C.demo2
+func cdemo2(int32, empty) int32
+
+func demo2(v int32, a empty) int32 {
+	return v
+}
+
+func init() {
+	assert("cdemo2", cdemo2(100, empty{}) == 100)
+	assert("demo2", demo2(100, empty{}) == 100)
+}
+
+//go:linkname cdemo3 C.demo3
+func cdemo3(int32, empty, int32) int32
+
+func demo3(v int32, a empty, v2 int32) int32 {
+	return v + v2
+}
+
+func init() {
+	assert("cdemo3", cdemo3(1, empty{}, 100) == 101)
+	assert("demo3", demo3(1, empty{}, 100) == 101)
+}
diff --git a/internal/cabi/_testdata/wrap/empty.c b/internal/cabi/_testdata/wrap/empty.c
new file mode 100644
index 00000000..558b2fed
--- /dev/null
+++ b/internal/cabi/_testdata/wrap/empty.c
@@ -0,0 +1,14 @@
+struct empty {
+};
+
+struct empty demo1(struct empty a) {
+    return a;
+}
+
+int demo2(int v, struct empty a) {
+    return v;
+}
+
+int demo3(int v, struct empty a, int v2) {
+    return v + v2;
+}
\ No newline at end of file
diff --git a/internal/cabi/arch.go b/internal/cabi/arch.go
index 393eea54..7c1b0e79 100644
--- a/internal/cabi/arch.go
+++ b/internal/cabi/arch.go
@@ -78,7 +78,6 @@ func (p *TypeInfoAmd64) GetTypeInfo(ctx llvm.Context, typ llvm.Type, bret bool)
 	if typ.TypeKind() == llvm.VoidTypeKind {
 		info.Kind = AttrVoid
 		return info
-	} else if typ.TypeKind() == llvm.PointerTypeKind {
 	}
 	info.Size = p.Sizeof(typ)
 	info.Align = p.Alignof(typ)
diff --git a/internal/cabi/cabi.go b/internal/cabi/cabi.go
index 4490a580..8b755139 100644
--- a/internal/cabi/cabi.go
+++ b/internal/cabi/cabi.go
@@ -128,11 +128,11 @@ type TypeInfoSys interface {
 type AttrKind int
 
 const (
-	AttrNone       AttrKind = iota
-	AttrVoid                // return type void
-	AttrPointer             // type => type*
-	AttrWidthType           // type => width int i16/i24/i32/i40/i48/i56/i64 float/double
-	AttrWidthType2          // type => width two int {i64,i16} float/double
+	AttrNone       AttrKind = iota // keep org type
+	AttrVoid                       // return type void / param type void (size == 0) skip
+	AttrPointer                    // type => type*
+	AttrWidthType                  // type => width int i16/i24/i32/i40/i48/i56/i64 float/double
+	AttrWidthType2                 // type => width two int {i64,i16} float/double
 )
 
 type FuncInfo struct {
@@ -146,7 +146,7 @@ func (p *FuncInfo) HasWrap() bool {
 		return true
 	}
 	for _, t := range p.Params {
-		if t.Kind > AttrVoid {
+		if t.Kind > AttrNone {
 			return true
 		}
 	}
@@ -178,6 +178,9 @@ func funcInlineHint(ctx llvm.Context) llvm.Attribute {
 
 func (p *Transformer) IsWrapType(ctx llvm.Context, typ llvm.Type, bret bool) bool {
 	if p.sys != nil {
+		if !bret && (typ.TypeKind() == llvm.VoidTypeKind || p.Sizeof(typ) == 0) {
+			return true
+		}
 		return p.sys.IsWrapType(ctx, typ, bret)
 	}
 	return false
@@ -185,6 +188,14 @@ func (p *Transformer) IsWrapType(ctx llvm.Context, typ llvm.Type, bret bool) boo
 
 func (p *Transformer) GetTypeInfo(ctx llvm.Context, typ llvm.Type, bret bool) *TypeInfo {
 	if p.sys != nil {
+		if typ.TypeKind() == llvm.VoidTypeKind {
+			return &TypeInfo{Type: typ, Kind: AttrVoid, Type1: ctx.VoidType()}
+		} else if p.Sizeof(typ) == 0 {
+			if bret {
+				return &TypeInfo{Type: typ, Kind: AttrNone, Type1: typ}
+			}
+			return &TypeInfo{Type: typ, Kind: AttrVoid, Type1: ctx.VoidType()}
+		}
 		return p.sys.GetTypeInfo(ctx, typ, bret)
 	}
 	panic("not implment: " + p.GOARCH)
@@ -228,6 +239,8 @@ func (p *Transformer) transformFuncType(ctx llvm.Context, info *FuncInfo) (llvm.
 
 	for _, ti := range info.Params {
 		switch ti.Kind {
+		case AttrVoid:
+			// skip
 		case AttrNone, AttrWidthType:
 			paramTypes = append(paramTypes, ti.Type1)
 		case AttrPointer:
@@ -294,9 +307,15 @@ func (p *Transformer) transformFuncBody(ctx llvm.Context, info *FuncInfo, fn llv
 		index++
 	}
 	for i, ti := range info.Params {
-		nv := params[index]
+		var nv llvm.Value
 		switch ti.Kind {
 		default:
+			nv = params[index]
+		case AttrVoid:
+			nv = llvm.ConstNull(ti.Type)
+			fn.Param(i).ReplaceAllUsesWith(nv)
+			// skip
+			continue
 		case AttrPointer:
 			nv = b.CreateLoad(ti.Type, params[index], "")
 		case AttrWidthType:
@@ -366,6 +385,8 @@ func (p *Transformer) transformCallInstr(ctx llvm.Context, call llvm.Value) bool
 		switch ti.Kind {
 		default:
 			nparams = append(nparams, param)
+		case AttrVoid:
+			// none
 		case AttrPointer:
 			ptr := llvm.CreateAlloca(b, ti.Type)
 			b.CreateStore(param, ptr)
@@ -510,6 +531,8 @@ func (p *Transformer) transformCallbackFunc(m llvm.Module, fn llvm.Value) (wrap
 	for _, ti := range info.Params {
 		switch ti.Kind {
 		default:
+		case AttrVoid:
+			// none
 		case AttrPointer:
 			nparams = append(nparams, b.CreateLoad(ti.Type, params[index], ""))
 		case AttrWidthType:
diff --git a/internal/cabi/cabi_test.go b/internal/cabi/cabi_test.go
index 7754fd5b..92fc75bc 100644
--- a/internal/cabi/cabi_test.go
+++ b/internal/cabi/cabi_test.go
@@ -128,7 +128,7 @@ func testFunc(t *testing.T, ctx context, td llvm.TargetData, fn llvm.Value, cfn
 		t.Fatalf("%v %v: bad param type %v != %v", ctx, fn.Name(), ft, cft)
 	}
 	for i, pt := range pts {
-		if !checkType(td, pt, cpts[i]) {
+		if !checkType(td, pt, cpts[i], false) {
 			t.Fatalf("%v %v: bad param type %v != %v", ctx, fn.Name(), ft, cft)
 		}
 		if i == 0 {
@@ -140,18 +140,25 @@ func testFunc(t *testing.T, ctx context, td llvm.TargetData, fn llvm.Value, cfn
 			t.Fatalf("%v %v: bad param attr type %v != %v", ctx, fn.Name(), ft, cft)
 		}
 	}
-	if !checkType(td, ft.ReturnType(), cft.ReturnType()) {
+	if !checkType(td, ft.ReturnType(), cft.ReturnType(), true) {
 		t.Fatalf("%v %v: bad return type %v != %v", ctx, fn.Name(), ft, cft)
 	}
 }
 
-func checkType(td llvm.TargetData, ft llvm.Type, cft llvm.Type) bool {
+func checkType(td llvm.TargetData, ft llvm.Type, cft llvm.Type, bret bool) bool {
 	if ft == cft {
 		return true
 	}
-	if ft.TypeKind() == llvm.VoidTypeKind && cft.TypeKind() == llvm.VoidTypeKind {
+	if bret {
+		if ft.TypeKind() == llvm.VoidTypeKind && (cft.TypeKind() == llvm.VoidTypeKind || td.TypeAllocSize(cft) == 0) {
+			return true
+		} else if cft.TypeKind() == llvm.VoidTypeKind && (ft.TypeKind() == llvm.VoidTypeKind || td.TypeAllocSize(ft) == 0) {
+			return true
+		}
+	} else if ft.TypeKind() == llvm.VoidTypeKind && cft.TypeKind() == llvm.VoidTypeKind {
 		return true
-	} else if ft.TypeKind() == llvm.VoidTypeKind || cft.TypeKind() == llvm.VoidTypeKind {
+	}
+	if ft.TypeKind() == llvm.VoidTypeKind || cft.TypeKind() == llvm.VoidTypeKind {
 		return false
 	}
 	if td.ABITypeAlignment(ft) != td.ABITypeAlignment(cft) {
@@ -169,7 +176,7 @@ func checkType(td llvm.TargetData, ft llvm.Type, cft llvm.Type) bool {
 		return true
 	}
 	for i, t := range et {
-		if !checkType(td, t, cet[i]) {
+		if !checkType(td, t, cet[i], bret) {
 			return false
 		}
 	}