Fix mistakenly derive hash for struct that contains IncompleteArrayField

src/ir/analysis/derive_hash.rs

@@ -187,7 +187,10 @@ impl<'ctx> MonotoneFramework for CannotDeriveHash<'ctx> {
                     return self.insert(id);
                 }
 
-                if len <= RUST_DERIVE_IN_ARRAY_LIMIT {
+                if len == 0 {
+                    trace!("    cannot derive `Hash` for incomplete arrays");
+                    self.insert(id)
+                } else if len <= RUST_DERIVE_IN_ARRAY_LIMIT {
                     trace!("    array is small enough to derive Hash");
                     ConstrainResult::Same
                 } else {

tests/expectations/tests/class.rs

@@ -142,6 +142,47 @@ impl Default for C_with_zero_length_array {
     }
 }
 #[repr(C)]
+#[derive(Debug, Default)]
+pub struct C_with_zero_length_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_zero_length_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_zero_length_array_2>(),
+        4usize,
+        concat!("Size of: ", stringify!(C_with_zero_length_array_2))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_zero_length_array_2>(),
+        4usize,
+        concat!("Alignment of ", stringify!(C_with_zero_length_array_2))
+    );
+    assert_eq!(
+        unsafe { &(*(0 as *const C_with_zero_length_array_2)).a as *const _ as usize },
+        0usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(C_with_zero_length_array_2),
+            "::",
+            stringify!(a)
+        )
+    );
+    assert_eq!(
+        unsafe {
+            &(*(0 as *const C_with_zero_length_array_2)).zero_length_array as *const _ as usize
+        },
+        4usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(C_with_zero_length_array_2),
+            "::",
+            stringify!(zero_length_array)
+        )
+    );
+}
+#[repr(C)]
 pub struct C_with_incomplete_array {
     pub a: ::std::os::raw::c_int,
     pub big_array: [::std::os::raw::c_char; 33usize],
@@ -166,6 +207,25 @@ impl Default for C_with_incomplete_array {
     }
 }
 #[repr(C)]
+#[derive(Debug, Default)]
+pub struct C_with_incomplete_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_incomplete_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_incomplete_array_2>(),
+        4usize,
+        concat!("Size of: ", stringify!(C_with_incomplete_array_2))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_incomplete_array_2>(),
+        4usize,
+        concat!("Alignment of ", stringify!(C_with_incomplete_array_2))
+    );
+}
+#[repr(C)]
 pub struct C_with_zero_length_array_and_incomplete_array {
     pub a: ::std::os::raw::c_int,
     pub big_array: [::std::os::raw::c_char; 33usize],
@@ -197,7 +257,33 @@ impl Default for C_with_zero_length_array_and_incomplete_array {
     }
 }
 #[repr(C)]
-#[derive(Debug, Default, Hash, PartialEq, Eq)]
+#[derive(Debug, Default)]
+pub struct C_with_zero_length_array_and_incomplete_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_zero_length_array_and_incomplete_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_zero_length_array_and_incomplete_array_2>(),
+        4usize,
+        concat!(
+            "Size of: ",
+            stringify!(C_with_zero_length_array_and_incomplete_array_2)
+        )
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_zero_length_array_and_incomplete_array_2>(),
+        4usize,
+        concat!(
+            "Alignment of ",
+            stringify!(C_with_zero_length_array_and_incomplete_array_2)
+        )
+    );
+}
+#[repr(C)]
+#[derive(Debug, Default, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct WithDtor {
     pub b: ::std::os::raw::c_int,
 }
@@ -336,7 +422,7 @@ impl Default for WithUnion {
     }
 }
 #[repr(C)]
-#[derive(Debug, Default, Copy, Hash, PartialEq, Eq)]
+#[derive(Debug, Default, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct RealAbstractionWithTonsOfMethods {
     pub _address: u8,
 }

tests/expectations/tests/class_1_0.rs

@@ -190,6 +190,47 @@ impl Default for C_with_zero_length_array {
     }
 }
 #[repr(C)]
+#[derive(Debug, Default)]
+pub struct C_with_zero_length_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_zero_length_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_zero_length_array_2>(),
+        4usize,
+        concat!("Size of: ", stringify!(C_with_zero_length_array_2))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_zero_length_array_2>(),
+        4usize,
+        concat!("Alignment of ", stringify!(C_with_zero_length_array_2))
+    );
+    assert_eq!(
+        unsafe { &(*(0 as *const C_with_zero_length_array_2)).a as *const _ as usize },
+        0usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(C_with_zero_length_array_2),
+            "::",
+            stringify!(a)
+        )
+    );
+    assert_eq!(
+        unsafe {
+            &(*(0 as *const C_with_zero_length_array_2)).zero_length_array as *const _ as usize
+        },
+        4usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(C_with_zero_length_array_2),
+            "::",
+            stringify!(zero_length_array)
+        )
+    );
+}
+#[repr(C)]
 pub struct C_with_incomplete_array {
     pub a: ::std::os::raw::c_int,
     pub big_array: [::std::os::raw::c_char; 33usize],
@@ -214,6 +255,25 @@ impl Default for C_with_incomplete_array {
     }
 }
 #[repr(C)]
+#[derive(Debug, Default)]
+pub struct C_with_incomplete_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_incomplete_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_incomplete_array_2>(),
+        4usize,
+        concat!("Size of: ", stringify!(C_with_incomplete_array_2))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_incomplete_array_2>(),
+        4usize,
+        concat!("Alignment of ", stringify!(C_with_incomplete_array_2))
+    );
+}
+#[repr(C)]
 pub struct C_with_zero_length_array_and_incomplete_array {
     pub a: ::std::os::raw::c_int,
     pub big_array: [::std::os::raw::c_char; 33usize],
@@ -245,6 +305,32 @@ impl Default for C_with_zero_length_array_and_incomplete_array {
     }
 }
 #[repr(C)]
+#[derive(Debug, Default)]
+pub struct C_with_zero_length_array_and_incomplete_array_2 {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_C_with_zero_length_array_and_incomplete_array_2() {
+    assert_eq!(
+        ::std::mem::size_of::<C_with_zero_length_array_and_incomplete_array_2>(),
+        4usize,
+        concat!(
+            "Size of: ",
+            stringify!(C_with_zero_length_array_and_incomplete_array_2)
+        )
+    );
+    assert_eq!(
+        ::std::mem::align_of::<C_with_zero_length_array_and_incomplete_array_2>(),
+        4usize,
+        concat!(
+            "Alignment of ",
+            stringify!(C_with_zero_length_array_and_incomplete_array_2)
+        )
+    );
+}
+#[repr(C)]
 #[derive(Debug, Default, Hash, PartialEq, Eq)]
 pub struct WithDtor {
     pub b: ::std::os::raw::c_int,

tests/expectations/tests/derive-hash-struct-with-incomplete-array.rs

@@ -0,0 +1,121 @@
+/* automatically generated by rust-bindgen */
+
+
+#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+
+
+#[repr(C)]
+#[derive(Default)]
+pub struct __IncompleteArrayField<T>(::std::marker::PhantomData<T>);
+impl<T> __IncompleteArrayField<T> {
+    #[inline]
+    pub fn new() -> Self {
+        __IncompleteArrayField(::std::marker::PhantomData)
+    }
+    #[inline]
+    pub unsafe fn as_ptr(&self) -> *const T {
+        ::std::mem::transmute(self)
+    }
+    #[inline]
+    pub unsafe fn as_mut_ptr(&mut self) -> *mut T {
+        ::std::mem::transmute(self)
+    }
+    #[inline]
+    pub unsafe fn as_slice(&self, len: usize) -> &[T] {
+        ::std::slice::from_raw_parts(self.as_ptr(), len)
+    }
+    #[inline]
+    pub unsafe fn as_mut_slice(&mut self, len: usize) -> &mut [T] {
+        ::std::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
+    }
+}
+impl<T> ::std::fmt::Debug for __IncompleteArrayField<T> {
+    fn fmt(&self, fmt: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
+        fmt.write_str("__IncompleteArrayField")
+    }
+}
+impl<T> ::std::clone::Clone for __IncompleteArrayField<T> {
+    #[inline]
+    fn clone(&self) -> Self {
+        Self::new()
+    }
+}
+impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
+#[repr(C)]
+#[derive(Debug, Default)]
+pub struct test {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_test() {
+    assert_eq!(
+        ::std::mem::size_of::<test>(),
+        4usize,
+        concat!("Size of: ", stringify!(test))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<test>(),
+        4usize,
+        concat!("Alignment of ", stringify!(test))
+    );
+    assert_eq!(
+        unsafe { &(*(0 as *const test)).a as *const _ as usize },
+        0usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(test),
+            "::",
+            stringify!(a)
+        )
+    );
+    assert_eq!(
+        unsafe { &(*(0 as *const test)).zero_length_array as *const _ as usize },
+        4usize,
+        concat!(
+            "Alignment of field: ",
+            stringify!(test),
+            "::",
+            stringify!(zero_length_array)
+        )
+    );
+}
+#[repr(C)]
+#[derive(Debug, Default)]
+pub struct test2 {
+    pub a: ::std::os::raw::c_int,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_test2() {
+    assert_eq!(
+        ::std::mem::size_of::<test2>(),
+        4usize,
+        concat!("Size of: ", stringify!(test2))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<test2>(),
+        4usize,
+        concat!("Alignment of ", stringify!(test2))
+    );
+}
+#[repr(C)]
+#[derive(Debug, Default)]
+pub struct test3 {
+    pub a: ::std::os::raw::c_int,
+    pub zero_length_array: __IncompleteArrayField<::std::os::raw::c_char>,
+    pub incomplete_array: __IncompleteArrayField<::std::os::raw::c_char>,
+}
+#[test]
+fn bindgen_test_layout_test3() {
+    assert_eq!(
+        ::std::mem::size_of::<test3>(),
+        4usize,
+        concat!("Size of: ", stringify!(test3))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<test3>(),
+        4usize,
+        concat!("Alignment of ", stringify!(test3))
+    );
+}