[gcc/devel/rust/master] libproc_macro: Custom Clone for Ident

[gcc/devel/rust/master] libproc_macro: Custom Clone for Ident

[Thomas Schwinge]

https://gcc.gnu.org/g:acf5db71524e56aef7a0071be96299b976760454

commit acf5db71524e56aef7a0071be96299b976760454
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Tue Feb 21 12:18:41 2023 +0100

    libproc_macro: Custom Clone for Ident
    
    The internal Ident structure contains a foreign allocated byte array,
    it's Clone trait cannot be derived automatically as the array would not
    be cloned correctly, only the pointer. This would lead to use
    after-free.
    
    ChangeLog:
    
            * librust/proc_macro/rust/bridge/ident.rs: Implement Clone for
            Ident.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 librust/proc_macro/rust/bridge/ident.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/librust/proc_macro/rust/bridge/ident.rs b/librust/proc_macro/rust/bridge/ident.rs
index 1c08a003e02..dbfa649d923 100644
--- a/librust/proc_macro/rust/bridge/ident.rs
+++ b/librust/proc_macro/rust/bridge/ident.rs
@@ -7,10 +7,11 @@ extern "C" {
     fn Ident__new(string: *const c_uchar, len: u64) -> Ident;
     fn Ident__new_raw(string: *const c_uchar, len: u64) -> Ident;
     fn Ident__drop(ident: *const Ident);
+    fn Ident__clone(ident: *const Ident) -> Ident;
 }
 
 #[repr(C)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct Ident {
     pub(crate) is_raw: bool,
     pub(crate) val: *const c_uchar,
@@ -59,3 +60,9 @@ impl fmt::Display for Ident {
         )
     }
 }
+
+impl Clone for Ident {
+    fn clone(&self) -> Self {
+        unsafe { Ident__clone(self as *const Ident) }
+    }
+}