File ondselsolver_fix_gcc_75_filesystem.patch of Package FreeCAD

From 2e3659c4bce3e6885269e0cb3d640261b2a91108 Mon Sep 17 00:00:00 2001
From: huguesdpdn <huguesdpdn.aerospace@gmail.com>
Date: Mon, 4 Nov 2024 16:00:12 +0100
Subject: [PATCH] Fix compilation under gcc7.5 (#81)

* Correct typo in individual license file name

* Fix compilation under GCC 7.5 for Ubuntu
---
 OndselSolver/ASMTAssembly.cpp     | 5 +++++
 OndselSolverMain/OndselSolver.cpp | 1 -
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/OndselSolver/ASMTAssembly.cpp b/OndselSolver/ASMTAssembly.cpp
index 9daf755..0f3dd1d 100644
--- a/OndselSolver/ASMTAssembly.cpp
+++ b/OndselSolver/ASMTAssembly.cpp
@@ -62,7 +62,9 @@
 #include "ASMTRotationLimit.h"
 #include "ASMTTranslationLimit.h"
 #include "ExternalSystem.h"
+#if __GNUC__ >= 8
 #include <filesystem>
+#endif
 
 using namespace MbD;
 
@@ -359,8 +361,11 @@ void MbD::ASMTAssembly::runSinglePendulum()
 
 std::shared_ptr<ASMTAssembly> MbD::ASMTAssembly::assemblyFromFile(const std::string& fileName)
 {
+    // https://stackoverflow.com/a/45867491
+    #if __GNUC__ >= 8
     std::filesystem::path currentPath = std::filesystem::current_path();
     std::cout << "Current directory: " << currentPath << std::endl;
+    #endif
 
     std::ifstream stream(fileName);
     if (stream.fail()) {
diff --git a/OndselSolverMain/OndselSolver.cpp b/OndselSolverMain/OndselSolver.cpp
index d4b82d9..97ab5b9 100644
--- a/OndselSolverMain/OndselSolver.cpp
+++ b/OndselSolverMain/OndselSolver.cpp
@@ -12,7 +12,6 @@
   * @brief Program to assemble a piston crank system.
   *********************************************************************/
 
-#include <filesystem>
 #include "../OndselSolver/CADSystem.h"
 #include "../OndselSolver/CREATE.h"
 #include "../OndselSolver/GESpMatParPvPrecise.h"