diff --git a/src/gflags.h.in b/src/gflags.h.in
index 43b3f7a..82e640f 100644
--- a/src/gflags.h.in
+++ b/src/gflags.h.in
@@ -86,7 +86,7 @@
 
 // We always want to export variables defined in user code
 #ifndef GFLAGS_DLL_DEFINE_FLAG
-#  ifdef _MSC_VER
+#  if GFLAGS_IS_A_DLL && defined(_MSC_VER)
 #    define GFLAGS_DLL_DEFINE_FLAG __declspec(dllexport)
 #  else
 #    define GFLAGS_DLL_DEFINE_FLAG