gvc: add storage-class attribute declaration of gvrender_ptf to gvcproc.h

This will allow removing this symbol from gvc.def in an upcoming commit.

Note that no other symbols from gvcproc.h were exported from gvc.def,
hence the attributes are applied only to gvrender_ptf.

Towards https://gitlab.com/graphviz/graphviz/-/issues/2058.

diff --git a/lib/gvc/gvcproc.h b/lib/gvc/gvcproc.h
index 447a0436df93d89a5e1551d12b28dbd30b33d562..215b21f8d131eae8588e019996b439d6687ccf55 100644 (file)
--- a/lib/gvc/gvcproc.h
+++ b/lib/gvc/gvcproc.h
@@ -67,7 +67,15 @@
 
 /* render */
 
+#ifdef GVDLL
+#ifdef GVC_EXPORTS
+    __declspec(dllexport) pointf gvrender_ptf(GVJ_t *job, pointf p);
+#else
+    __declspec(dllimport) pointf gvrender_ptf(GVJ_t *job, pointf p);
+#endif
+#else
     pointf gvrender_ptf(GVJ_t *job, pointf p);
+#endif
     pointf* gvrender_ptf_A(GVJ_t *job, pointf *af, pointf *AF, int n);
 
     int gvrender_begin_job(GVJ_t * job);