From 98cd9e8926fb03da962b33437493f6ddfe4d6f17 Mon Sep 17 00:00:00 2001
From: Paul Gustafson <paul.gustafson@gmail.com>
Date: Mon, 27 Nov 2023 18:37:44 -0800
Subject: [PATCH] Add assertion to prevent nonsense mod values (#2474)

---
 test/unit/test_symbolic.py | 6 ++++++
 tinygrad/shape/symbolic.py | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/test/unit/test_symbolic.py b/test/unit/test_symbolic.py
index 673657d1d1..03750d8acf 100644
--- a/test/unit/test_symbolic.py
+++ b/test/unit/test_symbolic.py
@@ -402,6 +402,12 @@ class TestSymbolicSymbolicOps(unittest.TestCase):
     with self.assertRaises(AssertionError):
       lt3 = (x < 3)
 
+  def test_nested_variable_mod(self):
+    i = Variable("i", 1, 5)
+    idx0 = Variable("idx0", 0, i)
+    with self.assertRaises(AssertionError):
+      assert idx0 % 2 == idx0
+
   def test_num_node_mul_node(self):
     a = Variable("a", 1, 5)
     b = NumNode(2) * a
diff --git a/tinygrad/shape/symbolic.py b/tinygrad/shape/symbolic.py
index 87062e012f..f8813d09a5 100644
--- a/tinygrad/shape/symbolic.py
+++ b/tinygrad/shape/symbolic.py
@@ -94,7 +94,7 @@ class Node:
       if self == b: return NumNode(0)
       if (b - self).min > 0 and self.min >= 0: return self # b - self simplifies the node
       raise RuntimeError(f"not supported: {self} % {b}")
-    assert b > 0
+    assert b > 0 and isinstance(self.max, int) and isinstance(self.min, int), 'not supported'
     if b == 1: return NumNode(0)
     if self.min >= 0 and self.max < b: return self
     if (self.min//b) == (self.max//b): return self - (b*(self.min//b))