diff --git a/src/common/filesystem/include/fs_filesystem.h b/src/common/filesystem/include/fs_filesystem.h
index b559494084..bac46e1bb0 100644
--- a/src/common/filesystem/include/fs_filesystem.h
+++ b/src/common/filesystem/include/fs_filesystem.h
@@ -202,7 +202,7 @@ protected:
 	int IwadIndex = -1;
 	int MaxIwadIndex = -1;
 
-	StringPool* stringpool;
+	StringPool* stringpool = nullptr;
 
 private:
 	void DeleteAll();
diff --git a/src/common/filesystem/source/file_directory.cpp b/src/common/filesystem/source/file_directory.cpp
index 84679ffc91..89b9625fc6 100644
--- a/src/common/filesystem/source/file_directory.cpp
+++ b/src/common/filesystem/source/file_directory.cpp
@@ -96,7 +96,7 @@ FDirectory::FDirectory(const char * directory, StringPool* sp, bool nosubdirflag
 {
 	auto fn = FS_FullPath(directory);
 	if (fn.back() != '/') fn += '/';
-	FileName = sp->Strdup(fn.c_str());
+	FileName = stringpool->Strdup(fn.c_str());
 }
 
 //==========================================================================
diff --git a/src/common/filesystem/source/filesystem.cpp b/src/common/filesystem/source/filesystem.cpp
index c22682ec0a..cc810cc2e2 100644
--- a/src/common/filesystem/source/filesystem.cpp
+++ b/src/common/filesystem/source/filesystem.cpp
@@ -194,8 +194,6 @@ static void PrintLastError (FileSystemMessageFunc Printf);
 
 FileSystem::FileSystem()
 {
-	stringpool = new StringPool(true);
-	stringpool->shared = true;	// will be used by all owned resource files.
 }
 
 FileSystem::~FileSystem ()
@@ -219,7 +217,7 @@ void FileSystem::DeleteAll ()
 		delete Files[i];
 	}
 	Files.clear();
-	delete stringpool;
+	if (stringpool != nullptr) delete stringpool;
 	stringpool = nullptr;
 }
 
@@ -248,6 +246,9 @@ bool FileSystem::InitMultipleFiles (std::vector<std::string>& filenames, LumpFil
 	DeleteAll();
 	numfiles = 0;
 
+	stringpool = new StringPool(true);
+	stringpool->shared = true;	// will be used by all owned resource files.
+
 	// first, check for duplicates
 	if (allowduplicates)
 	{