Only try to clean stuff if kart model is unique

src/graphics/shader_files_manager.hpp

@@ -54,16 +54,16 @@ public:
     // ------------------------------------------------------------------------
     ~ShaderFilesManager()
     {
-        clearAllShaderFiles();
+        removeAllShaderFiles();
     }
     // ------------------------------------------------------------------------
-    void clearAllShaderFiles()
+    void removeAllShaderFiles()
     {
-        clearUnusedShaderFiles();
+        removeUnusedShaderFiles();
         assert(m_shader_files_loaded.empty());
     }
     // ------------------------------------------------------------------------
-    void clearUnusedShaderFiles()
+    void removeUnusedShaderFiles()
     {
         for (auto it = m_shader_files_loaded.begin();
              it != m_shader_files_loaded.end();)

src/karts/kart_properties.cpp

@@ -23,6 +23,7 @@
 #include "config/player_manager.hpp"
 #include "graphics/central_settings.hpp"
 #include "graphics/material_manager.hpp"
+#include "graphics/shader_files_manager.hpp"
 #include "graphics/stk_tex_manager.hpp"
 #include "graphics/sp/sp_shader_manager.hpp"
 #include "graphics/sp/sp_texture_manager.hpp"
@@ -112,10 +113,11 @@ KartProperties::KartProperties(const std::string &filename)
 KartProperties::~KartProperties()
 {
 #ifndef SERVER_ONLY
-    m_kart_model = nullptr;
+    if (CVS->isGLSL() && m_kart_model.use_count() == 1)
-    if (CVS->isGLSL())
     {
+        m_kart_model = nullptr;
         SP::SPShaderManager::get()->removeUnusedShaders();
+        ShaderFilesManager::getInstance()->removeUnusedShaderFiles();
         SP::SPTextureManager::get()->removeUnusedTextures();
     }
 #endif

src/utils/debug.cpp

@@ -251,7 +251,7 @@ bool handleContextMenuAction(s32 cmd_id)
         Log::info("Debug", "Reloading shaders...");
         SP::SPShaderManager::get()->unloadAll();
         ShaderBase::killShaders();
-        ShaderFilesManager::getInstance()->clearAllShaderFiles();
+        ShaderFilesManager::getInstance()->removeAllShaderFiles();
         SP::SPShaderManager::get()->initAll();
 #endif
         break;