diff --git a/flexdll.c b/flexdll.c
index b19fe2a..a90a11f 100644
--- a/flexdll.c
+++ b/flexdll.c
@@ -47,8 +47,11 @@ typedef struct dlunit {
 } dlunit;
 typedef void *resolver(void*, const char*);
 
-static int error = 0;
-static char error_buffer[256];
+#ifdef _MSC_VER
+#define __thread __declspec(thread)
+#endif
+static __thread int error = 0;
+static __thread char error_buffer[256];
 
 /* Emulate a low-level dlopen-like interface */