Origin:
https://sourceforge.net/p/mcj/tickets/184/
https://sourceforge.net/p/mcj/fig2dev/ci/ff9aba206a30288f456dfc91584a52ba9927b438/

--- a/fig2dev/read.c
+++ b/fig2dev/read.c
@@ -989,6 +989,14 @@ sanitize_lineobject(
 			    obj_name[l->type-2], line_no);
 		    return -1;
 		}
+		if (l->type == T_ARC_BOX && l->radius == 0) {
+			put_msg("A %s, but zero corner radius "
+					"at line %d - convert "
+					"to a rectangle.",
+					obj_name[l->type - 2],
+					line_no);
+			l->type = T_BOX;
+		}
 	    }
 	}
 
--- a/fig2dev/tests/read.at
+++ b/fig2dev/tests/read.at
@@ -99,6 +99,17 @@ EOF
 ])
 AT_CLEANUP
 
+AT_SETUP([convert an arc-box with zero radius to a box])
+AT_KEYWORDS(read.c arc-box)
+AT_CHECK([fig2dev -L pict2e <<EOF
+FIG_FILE_TOP
+2 4 1 1 0 0 50 -1 -1 4.0 0 0 0 0 0 5
+	0 0 300 0 300 300 0 300 0 0
+EOF
+],0,ignore,[A rectangle with rounded corners, but zero corner radius at line 11 - convert to a rectangle.
+])
+AT_CLEANUP
+
 AT_SETUP([fail on a malformed arc-box])
 AT_KEYWORDS(read.c malformed arc-box)
 AT_CHECK([fig2dev -L pict2e <<EOF