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, 15 insertions, 0 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes/E0697.md b/compiler/rustc_error_codes/src/error_codes/E0697.md
new file mode 100644
index 000000000..ab63d2e73
--- /dev/null
+++ b/compiler/rustc_error_codes/src/error_codes/E0697.md
@@ -0,0 +1,15 @@
+A closure has been used as `static`.
+
+Erroneous code example:
+
+```compile_fail,E0697
+fn main() {
+    static || {}; // used as `static`
+}
+```
+
+Closures cannot be used as `static`. They "save" the environment,
+and as such a static closure would save only a static environment
+which would consist only of variables with a static lifetime. Given
+this it would be better to use a proper function. The easiest fix
+is to remove the `static` keyword.