plugin/gd: use GVDLL instead of _WIN32 to enable dllexport storage-class attribute...

Towards https://gitlab.com/graphviz/graphviz/-/issues/2173.

diff --git a/plugin/gd/gvplugin_gd.c b/plugin/gd/gvplugin_gd.c
index ca49dff757a473166f27fdaf221930dcf3f01e42..63f5b60ca45aa54fa938034051cdbf67af798e3a 100644 (file)
--- a/plugin/gd/gvplugin_gd.c
+++ b/plugin/gd/gvplugin_gd.c
@@ -29,7 +29,7 @@ static gvplugin_api_t apis[] = {
     {(api_t)0, 0},
 };
 
-#ifdef _WIN32
+#ifdef GVDLL
 #define GVPLUGIN_GD_API __declspec(dllexport)
 #else
 #define GVPLUGIN_GD_API