Compiling with clang++ shows unused lambda capture errors

[ai-mannamalai]

Compiling with clang++ shows unused lambda capture errors.

CXXGraph/include/CXXGraph/Graph/Algorithm/BestFirstSearch_impl.hpp
@@ -151,15 +151,8 @@ const std::vector<Node<T>> Graph<T>::concurrency_breadth_first_search(
   int block_size = 1;
   int level = 1;
 
-  auto extract_tasks = [&level_tracker, &tracker_mutex, &assigned_tasks,
+  auto extract_tasks = [&assigned_tasks,
                         &num_tasks, &block_size]() -> std::pair<int, int> {
-    /*
-    std::lock_guard<std::mutex> tracker_guard(tracker_mutex);
-    int task_block_size = std::min(num_tasks - assigned_tasks,
-    block_size); std::pair<int,int> task_block{assigned_tasks,
-    assigned_tasks + task_block_size}; assigned_tasks += task_block_size;
-    return task_block;
-    */
     int start = assigned_tasks.fetch_add(block_size);
     int end = std::min(num_tasks, start + block_size);
     return {start, end};

CXXGraph/include/CXXGraph/Graph/Algorithm/CycleDetection_impl.hpp
@@ -59,7 +59,7 @@ bool Graph<T>::isCyclicDirectedGraphDFS() const {
                          shared<const Node<T>>)>
           isCyclicDFSHelper;
       isCyclicDFSHelper =
-          [this, &isCyclicDFSHelper](
+          [&isCyclicDFSHelper](
               const std::shared_ptr<AdjacencyMatrix<T>> adjMatrix,
               std::unordered_map<CXXGraph::id_t, nodeStates> &states,
               shared<const Node<T>> node) {

include/CXXGraph/Graph/Algorithm/FordFulkerson_impl.hpp
@@ -67,7 +67,7 @@ double Graph<T>::fordFulkersonMaxFlow(const Node<T> &source,
       nodeSet.begin(), nodeSet.end(),
       [&target](auto node) { return node->getUserId() == target.getUserId(); });
 
-  auto bfs_helper = [this, &source_node_ptr, &target_node_ptr, &parent,
+  auto bfs_helper = [&source_node_ptr, &target_node_ptr, &parent,
                      &weightMap]() -> bool {
     std::unordered_map<shared<const Node<T>>, bool, nodeHash<T>> visited;
     std::queue<shared<const Node<T>>> queue;
diff --git a/CXXGraph/include/CXXGraph/Graph/Algorithm/Kosaraju_impl.hpp b/CXXGraph/include/CXXGraph/Graph/Algorithm/Kosaraju_impl.hpp
index 40c162757..f8d362d3c 100644
--- a/CXXGraph/include/CXXGraph/Graph/Algorithm/Kosaraju_impl.hpp
+++ b/CXXGraph/include/CXXGraph/Graph/Algorithm/Kosaraju_impl.hpp
@@ -89,7 +89,7 @@ SCCResult<T> Graph<T>::kosaraju() const {
     visited.clear();
 
     std::function<void(shared<const Node<T>>, SCCResult<T>, int)> dfs_helper1 =
-        [this, &rev, &visited, &dfs_helper1](
+        [&rev, &visited, &dfs_helper1](
             shared<const Node<T>> source, SCCResult<T> result, int sccLabel) {
           // mark the vertex visited
           visited[source->getId()] = true;

CXXGraph/Partitioning/Utility/Globals.hpp
@@ -41,8 +41,8 @@ class Globals {
   const std::string print() const;
 
   // CONSTANT
-  const int SLEEP_LIMIT = 16;  // In microseconds
-  const int PLACES = 4;
+  static constexpr int SLEEP_LIMIT = 16;  // In microseconds
+  static constexpr int PLACES = 4;
 
   int numberOfPartition = 0;  // number of partitions
   // OPTIONAL

[redwanulsourav]

Can you please specify the steps to reproduce this issue?

I tried compiling examples/DijkstraExample with export CXX=/usr/bin/clang++ and export CC=/usr/bin/clang and then cmake .. to build the example, which worked fine for me.

Which commands did you use to compile the files?

[ai-mannamalai]

$ clang++ --std=c++17 demo.cpp -I/path/to/CXXGraph From: Redwanul Haque Sourave ***@***.***> Date: Monday, June 16, 2025 at 7:07 PM To: ZigRazor/CXXGraph ***@***.***> Cc: Muthu Annamalai ***@***.***>, Author ***@***.***> Subject: [EXTERNAL] Re: [ZigRazor/CXXGraph] Compiling with clang++ shows unused lambda capture errors (Issue #509) [https://avatars.githubusercontent.com/u/21361588?s=20&v=4]redwanulsourav left a comment (ZigRazor/CXXGraph#509)<#509 (comment)> Can you please specify the steps to reproduce this issue? I tried compiling examples/DijkstraExample with export CXX=/usr/bin/clang++ and export CC=/usr/bin/clang and then cmake .. to build the example, which worked fine for me. Which commands did you use to compile the files? — Reply to this email directly, view it on GitHub<#509 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APGLTDBFYDPSAR4T4ZVDBUT3D5Z35AVCNFSM6AAAAAB6HKHLNSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDSNZYGY4TCMBTGY>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[redwanulsourav]

I couldn't reproduced the issue on using BestFirstSearch. May I know ur clang version and your platform?

I used the following demo.cpp

#include <CXXGraph/CXXGraph.hpp>
#include <memory>

using std::make_shared;
// example taken from
// https://www.youtube.com/watch?v=B06q2yjr-Cc
int main() {
  CXXGraph::Node<int> node0("0", 0);
  CXXGraph::Node<int> node1("1", 1);
  CXXGraph::Node<int> node2("2", 2);
  CXXGraph::Node<int> node3("3", 3);
  CXXGraph::Node<int> node4("4", 4);

  CXXGraph::UndirectedWeightedEdge<int> edge1(1, node0, node1, 1);
  CXXGraph::UndirectedWeightedEdge<int> edge2(2, node0, node2, 2);
  CXXGraph::UndirectedWeightedEdge<int> edge3(3, node1, node2, 6);
  CXXGraph::UndirectedWeightedEdge<int> edge4(4, node1, node3, 4);
  CXXGraph::UndirectedWeightedEdge<int> edge5(5, node2, node3, 5);
  CXXGraph::UndirectedWeightedEdge<int> edge6(6, node3, node4, 3);

  CXXGraph::T_EdgeSet<int> edgeSet;
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge1));
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge2));
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge3));
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge4));
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge5));
  edgeSet.insert(make_shared<CXXGraph::UndirectedWeightedEdge<int>>(edge6));
  // Can print out the edges for debugging
  std::cout << edge1 << "\n";
  std::cout << edge2 << "\n";
  std::cout << edge3 << "\n";
  std::cout << edge4 << "\n";
  std::cout << edge5 << "\n";
  std::cout << edge6 << "\n";

  CXXGraph::Graph<int> graph(edgeSet);
  std::vector<CXXGraph::Node<int>> res = graph.concurrency_breadth_first_search(node0, 2);
  return 0;
}

Compiled with clang++ demo.cpp -I include/ -pthread -std=c++17

I also placed a debug statement in BestFirstSearch_impl.h and the debug message was printed.