diff --git a/TODO.FACTOR.txt b/TODO.FACTOR.txt
index 6f081e82ef..2f98471d44 100644
--- a/TODO.FACTOR.txt
+++ b/TODO.FACTOR.txt
@@ -25,3 +25,9 @@
 - if two tasks write to a unix stream, the buffer can overflow
 - font problem: http://iarc1.ece.utexas.edu/~erg/font-bug.JPG
 - make 3.4 bits>double an error
+
+- 2220.446049250313 [ dup float? [ tanh ] when ] 
+  - call and compile-1 give  C{ 0.0/0.0 0.0/0.0 }  0.0/0.0
+- 2.718281828459045e+19 [ dup float? [ sech ] when ]
+  - call/compile-1:  C{ 0.0/0.0 0.0/0.0 }  0.0
+- 0.0/0.0 next-power-of-2 causes gc forever