diff --git a/Source/Tools/Flax.Build/Projects/VisualStudio/VCProjectGenerator.cs b/Source/Tools/Flax.Build/Projects/VisualStudio/VCProjectGenerator.cs
index 4b7f49712..88670c138 100644
--- a/Source/Tools/Flax.Build/Projects/VisualStudio/VCProjectGenerator.cs
+++ b/Source/Tools/Flax.Build/Projects/VisualStudio/VCProjectGenerator.cs
@@ -133,6 +133,8 @@ namespace Flax.Build.Projects.VisualStudio
 
             // Per configuration options
             var buildToolPath = Utilities.MakePathRelativeTo(typeof(Builder).Assembly.Location, projectDirectory);
+            var preprocessorDefinitions = new HashSet<string>();
+            var includePaths = new HashSet<string>();
             foreach (var configuration in project.Configurations)
             {
                 var platform = Platform.GetPlatform(configuration.Platform);
@@ -140,11 +142,11 @@ namespace Flax.Build.Projects.VisualStudio
                 var target = configuration.Target;
                 var targetBuildOptions = configuration.TargetBuildOptions;
 
-                var preprocessorDefinitions = new HashSet<string>();
+                preprocessorDefinitions.Clear();
                 foreach (var e in targetBuildOptions.CompileEnv.PreprocessorDefinitions)
                     preprocessorDefinitions.Add(e);
 
-                var includePaths = new HashSet<string>();
+                includePaths.Clear();
                 foreach (var e in targetBuildOptions.CompileEnv.IncludePaths)
                     includePaths.Add(e);