From 51d4d47cdee529379e4474b979427d4df4e79e05 Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Fri, 17 Jan 2025 15:42:22 -0800
Subject: [PATCH] Clean up for loop item types

---
 include/sleipnir/autodiff/Expression.hpp      | 2 +-
 include/sleipnir/autodiff/ExpressionGraph.hpp | 8 ++++----
 include/sleipnir/autodiff/Jacobian.hpp        | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/sleipnir/autodiff/Expression.hpp b/include/sleipnir/autodiff/Expression.hpp
index f7e9627a..8c6ffa8f 100644
--- a/include/sleipnir/autodiff/Expression.hpp
+++ b/include/sleipnir/autodiff/Expression.hpp
@@ -672,7 +672,7 @@ inline constexpr void IntrusiveSharedPtrDecRefCount(Expression* expr) {
       if (elem->adjointExpr != nullptr) {
         stack.emplace_back(elem->adjointExpr.Get());
       }
-      for (auto&& arg : elem->args) {
+      for (auto& arg : elem->args) {
         if (arg != nullptr) {
           stack.emplace_back(arg.Get());
         }
diff --git a/include/sleipnir/autodiff/ExpressionGraph.hpp b/include/sleipnir/autodiff/ExpressionGraph.hpp
index 038cceef..57ebe8ad 100644
--- a/include/sleipnir/autodiff/ExpressionGraph.hpp
+++ b/include/sleipnir/autodiff/ExpressionGraph.hpp
@@ -46,7 +46,7 @@ class ExpressionGraph {
       auto node = stack.back();
       stack.pop_back();
 
-      for (auto&& arg : node->args) {
+      for (auto& arg : node->args) {
         // Only continue if the node is not a constant and hasn't already been
         // explored.
         if (arg != nullptr && arg->Type() != ExpressionType::kConstant) {
@@ -75,7 +75,7 @@ class ExpressionGraph {
         m_valueList.emplace_back(node);
       }
 
-      for (auto&& arg : node->args) {
+      for (auto& arg : node->args) {
         // Only add node if it's not a constant and doesn't already exist in the
         // tape.
         if (arg != nullptr && arg->Type() != ExpressionType::kConstant) {
@@ -144,7 +144,7 @@ class ExpressionGraph {
     // multiplied by dy/dx. If there are multiple "paths" from the root node to
     // variable; the variable's adjoint is the sum of each path's adjoint
     // contribution.
-    for (auto node : m_adjointList) {
+    for (auto& node : m_adjointList) {
       auto& lhs = node->args[0];
       auto& rhs = node->args[1];
 
@@ -166,7 +166,7 @@ class ExpressionGraph {
     // Unlink adjoints to avoid circular references between them and their
     // parent expressions. This ensures all expressions are returned to the free
     // list.
-    for (auto node : m_adjointList) {
+    for (auto& node : m_adjointList) {
       for (auto& arg : node->args) {
         if (arg != nullptr) {
           arg->adjointExpr = nullptr;
diff --git a/include/sleipnir/autodiff/Jacobian.hpp b/include/sleipnir/autodiff/Jacobian.hpp
index 6006db96..aff13c10 100644
--- a/include/sleipnir/autodiff/Jacobian.hpp
+++ b/include/sleipnir/autodiff/Jacobian.hpp
@@ -39,7 +39,7 @@ class SLEIPNIR_DLLEXPORT Jacobian {
       m_wrt(row).expr->row = row;
     }
 
-    for (Variable variable : m_variables) {
+    for (auto& variable : m_variables) {
       m_graphs.emplace_back(variable.expr);
     }