From e430f33e0ec05157ea2ca4bcc9bab57d6ef3b98b Mon Sep 17 00:00:00 2001
From: dalance <dalance@gmail.com>
Date: Wed, 26 Jun 2024 18:43:46 +0900
Subject: [PATCH] Fix stack overflow at symbol resolver

---
 crates/analyzer/src/symbol_table.rs |  7 +++++++
 crates/analyzer/src/tests.rs        | 13 +++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/crates/analyzer/src/symbol_table.rs b/crates/analyzer/src/symbol_table.rs
index 0aa6e4ad..9a6de7cc 100644
--- a/crates/analyzer/src/symbol_table.rs
+++ b/crates/analyzer/src/symbol_table.rs
@@ -107,6 +107,13 @@ impl SymbolTable {
         kind: &TypeKind,
     ) -> Result<ResolveContext<'a>, ResolveError> {
         if let TypeKind::UserDefined(ref x) = kind {
+            // Detect infinite loop in trace_user_defined
+            if let Some(last_found) = context.last_found {
+                if *x.first().unwrap() == last_found.token.text {
+                    return Ok(context);
+                }
+            }
+
             let symbol = self.resolve(&SymbolPath::new(x), &context.namespace)?;
             match symbol.found.kind {
                 SymbolKind::SystemVerilog => context.sv_member = true,
diff --git a/crates/analyzer/src/tests.rs b/crates/analyzer/src/tests.rs
index 467d34b8..7c3d5b76 100644
--- a/crates/analyzer/src/tests.rs
+++ b/crates/analyzer/src/tests.rs
@@ -2034,3 +2034,16 @@ fn r#unsafe() {
     let errors = analyze(code);
     assert!(matches!(errors[0], AnalyzerError::UnknownUnsafe { .. }));
 }
+
+#[test]
+fn detect_recursive() {
+    let code = r#"
+    module ModuleA (
+        x: input x,
+    ) {
+    }
+    "#;
+
+    let errors = analyze(code);
+    assert!(matches!(errors[0], AnalyzerError::MismatchType { .. }));
+}