diff -r e4ee0b15cc4f Lib/test/test_ast.py
--- a/Lib/test/test_ast.py	Wed Apr 16 23:32:21 2014 +0530
+++ b/Lib/test/test_ast.py	Thu Apr 17 11:17:32 2014 -0400
@@ -423,6 +423,16 @@
             compile(empty_yield_from, "<test>", "exec")
         self.assertIn("field value is required", str(cm.exception))
 
+    def test_binop_col_offset(self):
+        # Issue 18374: sequences of binops don't get correct col_offsets
+        tree = ast.parse('4+5+6+7')  # Check recursion beyond one level
+        parent_binop = tree.body[0].value
+        child_binop = parent_binop.left
+        grandchild_binop = child_binop.left
+        self.assertEqual(parent_binop.col_offset, 0)
+        self.assertEqual(child_binop.col_offset, 0)
+        self.assertEqual(grandchild_binop.col_offset, 0)
+
 
 class ASTHelpers_Test(unittest.TestCase):
 
diff -r e4ee0b15cc4f Python/Python-ast.c
--- a/Python/Python-ast.c	Wed Apr 16 23:32:21 2014 +0530
+++ b/Python/Python-ast.c	Thu Apr 17 11:17:32 2014 -0400
@@ -1621,7 +1621,15 @@
     p->v.BinOp.op = op;
     p->v.BinOp.right = right;
     p->lineno = lineno;
-    p->col_offset = col_offset;
+    if (p->v.BinOp.left->kind == BinOp_kind) {
+        /* Bug 18374: binops are left-associative, so the expr that generated
+         * this node actually started where its leftmost child started.
+         * Update our col_offset to match.
+         */
+        p->col_offset = p->v.BinOp.left->col_offset;
+    } else {
+        p->col_offset = col_offset;
+    }
     return p;
 }
 
diff -r e4ee0b15cc4f Python/compile.c
--- a/Python/compile.c	Wed Apr 16 23:32:21 2014 +0530
+++ b/Python/compile.c	Thu Apr 17 11:17:32 2014 -0400
@@ -3420,6 +3420,13 @@
     case BinOp_kind:
         VISIT(c, expr, e->v.BinOp.left);
         VISIT(c, expr, e->v.BinOp.right);
+        if (e->v.BinOp.left->kind == BinOp_kind) {
+            /* Bug 18374: binops are left-associative, so update this node's
+             * col_offset to start where the entire expression did.
+             */
+            e->col_offset = e->v.BinOp.left->col_offset;
+            c->u->u_col_offset = e->col_offset;
+        }
         ADDOP(c, binop(c, e->v.BinOp.op));
         break;
     case UnaryOp_kind: