[gcc r16-2876] gccrs: Implement compilation of IdentifierPattern's subpattern bindings

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:c11c65378d9a959fff53f0505e4457c239cfc6b8

commit r16-2876-gc11c65378d9a959fff53f0505e4457c239cfc6b8
Author: Zhi Heng <yapz...@gmail.com>
Date:   Fri Jun 13 22:45:23 2025 +0800

    gccrs: Implement compilation of IdentifierPattern's subpattern bindings
    
    gcc/rust/ChangeLog:
    
            * backend/rust-compile-pattern.cc: Add support for 
IdentifierPattern's
                    subpattern under CompilePatternBindings.
    
    Signed-off-by: Yap Zhi Heng <yapz...@gmail.com>

Diff:
---
 gcc/rust/backend/rust-compile-pattern.cc                  |  6 ++++++
 .../rust/compile/match-identifierpattern-enum.rs          | 12 ++++++++++++
 .../rust/execute/match-identifierpattern-enum.rs          | 15 +++++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/gcc/rust/backend/rust-compile-pattern.cc 
b/gcc/rust/backend/rust-compile-pattern.cc
index e19aa678497d..bd3aea01b537 100644
--- a/gcc/rust/backend/rust-compile-pattern.cc
+++ b/gcc/rust/backend/rust-compile-pattern.cc
@@ -666,6 +666,12 @@ CompilePatternBindings::visit (HIR::ReferencePattern 
&pattern)
 void
 CompilePatternBindings::visit (HIR::IdentifierPattern &pattern)
 {
+  if (pattern.has_subpattern ())
+    {
+      CompilePatternBindings::Compile (pattern.get_subpattern (),
+                                      match_scrutinee_expr, ctx);
+    }
+
   if (!pattern.get_is_ref ())
     {
       ctx->insert_pattern_binding (pattern.get_mappings ().get_hirid (),
diff --git a/gcc/testsuite/rust/compile/match-identifierpattern-enum.rs 
b/gcc/testsuite/rust/compile/match-identifierpattern-enum.rs
new file mode 100644
index 000000000000..c712667e27a4
--- /dev/null
+++ b/gcc/testsuite/rust/compile/match-identifierpattern-enum.rs
@@ -0,0 +1,12 @@
+enum Foo {
+    I(i32),
+}
+
+fn main() {
+    let x = Foo::I(1);
+
+    match x {
+        a @ Foo::I(b) => {},
+        _ => {},
+    };
+}
diff --git a/gcc/testsuite/rust/execute/match-identifierpattern-enum.rs 
b/gcc/testsuite/rust/execute/match-identifierpattern-enum.rs
new file mode 100644
index 000000000000..c3a0f65fe710
--- /dev/null
+++ b/gcc/testsuite/rust/execute/match-identifierpattern-enum.rs
@@ -0,0 +1,15 @@
+enum Foo {
+    I(i32),
+}
+
+fn main() -> i32 {
+    let x = Foo::I(0);
+    let ret = 1;
+
+    match x {
+        _ @ Foo::I(b) => { ret = b },
+        _ => {},
+    };
+
+    ret
+}