From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Sun, 16 Jun 2024 12:08:49 -0700
Subject: [PATCH 02/10] Use wpi::SmallVector

---
 include/sleipnir/autodiff/expression.hpp | 4 ++--
 include/sleipnir/autodiff/variable.hpp   | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/sleipnir/autodiff/expression.hpp b/include/sleipnir/autodiff/expression.hpp
index f04967c6a84ea76b77cebb7ef8edcb798d03e2a5..361c74702107eadf6f1fbe1682a7ef296abd19a3 100644
--- a/include/sleipnir/autodiff/expression.hpp
+++ b/include/sleipnir/autodiff/expression.hpp
@@ -34,7 +34,7 @@ struct Expression;
 template <typename Scalar>
 constexpr void inc_ref_count(Expression<Scalar>* expr);
 template <typename Scalar>
-constexpr void dec_ref_count(Expression<Scalar>* expr);
+void dec_ref_count(Expression<Scalar>* expr);
 
 /// Typedef for intrusive shared pointer to Expression.
 ///
@@ -749,7 +749,7 @@ constexpr void inc_ref_count(Expression<Scalar>* expr) {
 /// @tparam Scalar Scalar type.
 /// @param expr The shared pointer's managed object.
 template <typename Scalar>
-constexpr void dec_ref_count(Expression<Scalar>* expr) {
+void dec_ref_count(Expression<Scalar>* expr) {
   // If a deeply nested tree is being deallocated all at once, calling the
   // Expression destructor when expr's refcount reaches zero can cause a stack
   // overflow. Instead, we iterate over its children to decrement their
diff --git a/include/sleipnir/autodiff/variable.hpp b/include/sleipnir/autodiff/variable.hpp
index a6b054494a18eacbcae10c0e88648550a39ed48e..ad8baa3b58047f5257c210b88446324cca121d4a 100644
--- a/include/sleipnir/autodiff/variable.hpp
+++ b/include/sleipnir/autodiff/variable.hpp
@@ -58,7 +58,7 @@ class Variable : public SleipnirBase {
   Variable() = default;
 
   /// Constructs an empty Variable.
-  explicit constexpr Variable(std::nullptr_t) : expr{nullptr} {}
+  explicit Variable(std::nullptr_t) : expr{nullptr} {}
 
   /// Constructs a Variable from a scalar type.
   ///
@@ -101,7 +101,7 @@ class Variable : public SleipnirBase {
   /// Constructs a Variable pointing to the specified expression.
   ///
   /// @param expr The autodiff variable.
-  explicit constexpr Variable(detail::ExpressionPtr<Scalar>&& expr)
+  explicit Variable(detail::ExpressionPtr<Scalar>&& expr)
       : expr{std::move(expr)} {}
 
   /// Assignment operator for scalar.