Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes/E0366.md b/compiler/rustc_error_codes/src/error_codes/E0366.md
new file mode 100644
index 000000000..e6f8e6189
--- /dev/null
+++ b/compiler/rustc_error_codes/src/error_codes/E0366.md
@@ -0,0 +1,30 @@
+An attempt was made to implement `Drop` on a concrete specialization of a
+generic type. An example is shown below:
+
+```compile_fail,E0366
+struct Foo<T> {
+    t: T
+}
+
+impl Drop for Foo<u32> {
+    fn drop(&mut self) {}
+}
+```
+
+This code is not legal: it is not possible to specialize `Drop` to a subset of
+implementations of a generic type. One workaround for this is to wrap the
+generic type, as shown below:
+
+```
+struct Foo<T> {
+    t: T
+}
+
+struct Bar {
+    t: Foo<u32>
+}
+
+impl Drop for Bar {
+    fn drop(&mut self) {}
+}
+```