expansion: Expand generic args in generic type path segments

gcc/rust/ChangeLog:

	* expand/rust-expand-visitor.cc (ExpandVisitor::visit): Correctly visit the generic args
	of a generic type path segment.

gcc/testsuite/ChangeLog:

	* rust/compile/issue-2015.rs: New test.

2 files changed, 22 insertions, 1 deletions

diff --git a/gcc/rust/expand/rust-expand-visitor.cc b/gcc/rust/expand/rust-expand-visitor.cc
index 96677e3..b5e65b5 100644
--- a/gcc/rust/expand/rust-expand-visitor.cc
+++ b/gcc/rust/expand/rust-expand-visitor.cc
@@ -488,7 +488,9 @@ ExpandVisitor::visit (AST::PathInExpression &path)
 
 void
 ExpandVisitor::visit (AST::TypePathSegmentGeneric &segment)
-{}
+{
+  expand_generic_args (segment.get_generic_args ());
+}
 
 void
 ExpandVisitor::visit (AST::TypePathSegmentFunction &segment)
diff --git a/gcc/testsuite/rust/compile/issue-2015.rs b/gcc/testsuite/rust/compile/issue-2015.rs
new file mode 100644
index 0000000..7789ecd
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-2015.rs
@@ -0,0 +1,19 @@
+// { dg-additional-options "-frust-compile-until=lowering" }
+
+macro_rules! impl_foo {
+	() => { impl Foo }
+}
+
+pub trait Foo {}
+
+pub trait Bar {
+    type Baz;
+}
+
+pub fn foo(_value: impl Bar<Baz = impl_foo!()>) -> i32 {
+    15
+}
+
+pub fn bar(_value: impl Bar<Baz = impl Foo>) -> i32 {
+    16
+}