diff -up gv-3.7.4/src/zoom.c.bug1071238 gv-3.7.4/src/zoom.c --- gv-3.7.4/src/zoom.c.bug1071238 2012-03-29 10:03:50.000000000 -0600 +++ gv-3.7.4/src/zoom.c 2014-02-28 09:17:20.522332906 -0700 @@ -109,7 +109,7 @@ zoom_createZoom(Widget w _GL_UNUSED, XtP return; } - if (strcmp(gv_filename, "-")) { + if (gv_filename != NULL && strcmp(gv_filename, "-")) { stat(gv_filename, &sbuf); if (mtime != sbuf.st_mtime) { INFMESSAGE1(file has changed) ENDMESSAGE1(zoom_createZoom)return;