[PATCH 04/17] rust/vmstate: Use ident instead of expr to parse vmsd in vmstate_struct macro

[Zhao Liu]

When specify an array field in vmstate_struct macro, there will be an
error:

> local ambiguity when calling macro `vmstate_struct`: multiple parsing
> options: built-in NTs expr ('vmsd') or 1 other option.

This is because "expr" can't recognize the "vmsd" field correctly, so
that it gets confused with the previous array field.

To fix the above issue, use "ident" for "vmsd" field, and explicitly
refer to it in the macro.

Signed-off-by: Zhao Liu <zhao1....@intel.com>
---
 rust/hw/char/pl011/src/device_class.rs | 2 +-
 rust/qemu-api/src/vmstate.rs           | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/rust/hw/char/pl011/src/device_class.rs 
b/rust/hw/char/pl011/src/device_class.rs
index 0b2076ddaa0f..e43a5d6cd063 100644
--- a/rust/hw/char/pl011/src/device_class.rs
+++ b/rust/hw/char/pl011/src/device_class.rs
@@ -72,7 +72,7 @@ extern "C" fn pl011_post_load(opaque: *mut c_void, 
version_id: c_int) -> c_int {
     post_load: Some(pl011_post_load),
     fields: vmstate_fields! {
         vmstate_unused!(core::mem::size_of::<u32>()),
-        vmstate_struct!(PL011State, regs, &VMSTATE_PL011_REGS, 
BqlRefCell<PL011Registers>),
+        vmstate_struct!(PL011State, regs, VMSTATE_PL011_REGS, 
BqlRefCell<PL011Registers>),
     },
     subsections: vmstate_subsections! {
         VMSTATE_PL011_CLOCK
diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
index 94efbd8bb735..3f95d4825149 100644
--- a/rust/qemu-api/src/vmstate.rs
+++ b/rust/qemu-api/src/vmstate.rs
@@ -435,7 +435,7 @@ macro_rules! vmstate_unused {
 #[doc(alias = "VMSTATE_STRUCT")]
 #[macro_export]
 macro_rules! vmstate_struct {
-    ($struct_name:ty, $field_name:ident $(, [0 .. $num:ident $(* 
$factor:expr)?])?, $vmsd:expr, $type:ty $(,)?) => {
+    ($struct_name:ty, $field_name:ident $(, [0 .. $num:ident $(* 
$factor:expr)?])?, $vmsd:ident, $type:ty $(,)?) => {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), "\0")
                 .as_bytes()
@@ -447,7 +447,7 @@ macro_rules! vmstate_struct {
             },
             size: ::core::mem::size_of::<$type>(),
             flags: $crate::bindings::VMStateFlags::VMS_STRUCT,
-            vmsd: $vmsd,
+            vmsd: &$vmsd,
             ..$crate::zeroable::Zeroable::ZERO $(
                 .with_varray_flag($crate::call_func_with_field!(
                     $crate::vmstate::vmstate_varray_flag,
-- 
2.34.1