Bump Rust to 1.59.0

src/ir/dtype.rs

@@ -881,6 +881,7 @@ impl Dtype {
         }
     }
 
+    #[must_use]
     pub fn set_const(self, is_const: bool) -> Self {
         match self {
             Self::Unit { .. } => Self::Unit { is_const },
@@ -998,6 +999,7 @@ impl Dtype {
         }
     }
 
+    #[must_use]
     pub fn set_signed(self, is_signed: bool) -> Self {
         match self {
             Self::Int {

src/ir/interp.rs

@@ -1037,12 +1037,11 @@ impl Byte {
                 let padding = std::cmp::max(inner_size, inner_align) - inner_size;
                 values
                     .iter()
-                    .map(|v| {
+                    .flat_map(|v| {
                         let mut result = Self::value_to_bytes(v, structs);
                         result.extend(iter::repeat(Byte::Undef).take(padding));
                         result
                     })
-                    .flatten()
                     .collect()
             }
             Value::Struct { name, fields } => {

src/ir/mod.rs

@@ -740,6 +740,7 @@ impl Constant {
         matches!(self, Self::Undef { .. })
     }
 
+    #[must_use]
     pub fn typecast(self, target_dtype: Dtype) -> Self {
         if self.dtype() == target_dtype {
             return self;

src/ir/write_ir.rs

@@ -28,7 +28,7 @@ impl WriteLine for TranslationUnit {
                             } else {
                                 "%anon"
                             },
-                            f.deref().to_string()
+                            f.deref()
                         )
                     })
                     .collect::<Vec<_>>()