From c0e42bbfc889fd28138f000e2e8a5a1f53fcb46b Mon Sep 17 00:00:00 2001
From: whitequark <whitequark@whitequark.org>
Date: Thu, 16 Jun 2016 14:18:43 +0000
Subject: [PATCH] compiler.embedding: always do one final inference pass.

Fixes #477.
---
 artiq/compiler/embedding.py         |  5 +++++
 artiq/test/lit/embedding/bug_477.py | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 artiq/test/lit/embedding/bug_477.py

diff --git a/artiq/compiler/embedding.py b/artiq/compiler/embedding.py
index 491a2052e..f4a9bd4cb 100644
--- a/artiq/compiler/embedding.py
+++ b/artiq/compiler/embedding.py
@@ -613,6 +613,11 @@ class Stitcher:
                 break
             old_typedtree_hash = typedtree_hash
 
+        # When we have an excess of type information, sometimes we can infer every type
+        # in the AST without discovering every referenced attribute of host objects, so
+        # do one last pass unconditionally.
+        inferencer.visit(self.typedtree)
+
         # After we have found all functions, synthesize a module to hold them.
         source_buffer = source.Buffer("", "<synthesized>")
         self.typedtree = asttyped.ModuleT(
diff --git a/artiq/test/lit/embedding/bug_477.py b/artiq/test/lit/embedding/bug_477.py
new file mode 100644
index 000000000..19d496ca6
--- /dev/null
+++ b/artiq/test/lit/embedding/bug_477.py
@@ -0,0 +1,20 @@
+# RUN: %python -m artiq.compiler.testbench.embedding %s
+
+from artiq.experiment import *
+
+class MyClass:
+    def __init__(self, **kwargs):
+        for k, v in kwargs.items():
+            setattr(self, k, v)
+
+
+sl = [MyClass(x=1), MyClass(x=2)]
+
+@kernel
+def bug(l):
+    for c in l:
+        print(c.x)
+
+@kernel
+def entrypoint():
+    bug(sl)