Fixes for -fno-common
https://github.com/rubund/graywolf/commit/f47937b66d4d44eafc4224f7c43d556dbf88f05b

Index: src/twsc/config.h
--- src/twsc/config.h.orig
+++ src/twsc/config.h
@@ -34,7 +34,7 @@ EXTERN ROWBOX *rowArrayG ;
 
 EXTERN INT max_blklengthG ;
 EXTERN INT route2actG;   /* added for placement adjusted for routing */
-EXTERN INT track_pitchG; /* used only if global routing is performed */
+extern INT track_pitchG; /* used only if global routing is performed */
 EXTERN INT gridCellG;    /* used only if global routing is performed */
 EXTERN INT desiredLG ;
 EXTERN DOUBLE *macspaceG ;
