From 02da2cf4ae64908c9b7bb1b249a5975b18fa637c Mon Sep 17 00:00:00 2001
From: ringabout <43030857+ringabout@users.noreply.github.com>
Date: Wed, 29 Jul 2026 22:38:57 +0800
Subject: [PATCH] fixes #13736; Compiler crash with auto return type and
 recursion

---
 compiler/semcall.nim     |  4 ++++
 tests/errmsgs/t13736.nim | 12 ++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 tests/errmsgs/t13736.nim

diff --git a/compiler/semcall.nim b/compiler/semcall.nim
index 38b88ee7d2..f29af17777 100644
--- a/compiler/semcall.nim
+++ b/compiler/semcall.nim
@@ -918,6 +918,10 @@ proc semResolvedCall(c: PContext, x: var TCandidate,
   markUsed(c, info, finalCallee, isGenericInstance = true)
   onUse(info, finalCallee, isGenericInstance = true)
 
+  if finalCallee == c.p.owner and finalCallee.typ.returnType != nil and
+      finalCallee.typ.returnType.kind == tyAnything:
+    localError(c.config, info, "cannot infer type of recursive call")
+
   result = compactVoidArgs(x.call)
   instGenericConvertersSons(c, result, x)
   markConvertersUsed(c, result)
diff --git a/tests/errmsgs/t13736.nim b/tests/errmsgs/t13736.nim
new file mode 100644
index 0000000000..3625b034a5
--- /dev/null
+++ b/tests/errmsgs/t13736.nim
@@ -0,0 +1,12 @@
+discard """
+  errormsg: "cannot infer type of recursive call"
+  line: 8
+"""
+
+proc foo(n: int): auto =
+  if n < 5:
+    return foo(n + 1)
+  else:
+    return 9
+
+echo foo(3)