gccrs: Add lifetime name validation pass

Add lifetime name check in ast validation visitor.

gcc/rust/ChangeLog:

	* checks/errors/rust-ast-validation.cc (RS_TOKEN): Add keyword set.
	(RS_TOKEN_KEYWORD): Likewise.
	(ASTValidation::visit): Add validation on lifetime visit.
	* checks/errors/rust-ast-validation.h: Add function prototype.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

2 files changed, 24 insertions, 0 deletions

diff --git a/gcc/rust/checks/errors/rust-ast-validation.cc b/gcc/rust/checks/errors/rust-ast-validation.cc
index 92822fe..d27d3e8 100644
--- a/gcc/rust/checks/errors/rust-ast-validation.cc
+++ b/gcc/rust/checks/errors/rust-ast-validation.cc
@@ -21,6 +21,29 @@
 
 namespace Rust {
 
+namespace {
+// TODO: make constexpr when update to c++20
+const std::map<std::string, TokenId> keywords = {
+#define RS_TOKEN(x, y)
+#define RS_TOKEN_KEYWORD(tok, key) {key, tok},
+  RS_TOKEN_LIST
+#undef RS_TOKEN_KEYWORD
+#undef RS_TOKEN
+};
+} // namespace
+
+void
+ASTValidation::visit (AST::Lifetime &lifetime)
+{
+  auto name = lifetime.get_lifetime_name ();
+  auto valid = std::set<std::string>{"static", "_"};
+  if (valid.find (name) == valid.end ()
+      && keywords.find (name) != keywords.end ())
+    rust_error_at (lifetime.get_locus (), "lifetimes cannot use keyword names");
+
+  AST::ContextualASTVisitor::visit (lifetime);
+}
+
 void
 ASTValidation::visit (AST::ConstantItem &const_item)
 {
diff --git a/gcc/rust/checks/errors/rust-ast-validation.h b/gcc/rust/checks/errors/rust-ast-validation.h
index 1b1403f..ef0b2ac 100644
--- a/gcc/rust/checks/errors/rust-ast-validation.h
+++ b/gcc/rust/checks/errors/rust-ast-validation.h
@@ -34,6 +34,7 @@ public:
   void check (AST::Crate &crate) { AST::ContextualASTVisitor::visit (crate); }
 
   virtual void visit (AST::ConstantItem &const_item);
+  virtual void visit (AST::Lifetime &lifetime);
 };
 
 } // namespace Rust