It seems that the interpreter handles strangely the power series:

a:= series sin(x)

(1)

)di type a

   Type of value of a: Any
-- If I coerce it...
a:=a::UnivariatePuiseuxSeries(Expression Float,x,0)

(2)

)di type a

   Type of value of a: UnivariatePuiseuxSeries(Expression(Float),x,0.0)
a*1.0

(3)

---

Fatal bug:

 a:= series sin(x);
 a*1.0;
 >> System error:
 Caught fatal error [memory may be damaged]
 protected-symbol-warn called with (NIL)

From trace it seems that the interpreter doesn't coerce one args in Expression (Float):

  1<enter valueArgsEqual? : (|UnivariatePuiseuxSeries| (|Expression| (|Integer|)) |x| 
               ((0 . 0) 0 . 1))\
               (|UnivariatePuiseuxSeries| (|Expression| (|Float|)) |x| ((0 . 0) 0 . 1))
  ...

And here:

 1<enter algEqual : ((0 . 0) 0 . 1)\((0 0 . 0) 0 1 . 0)\(|Expression| (|Float|))
 1<enter compiledLookupCheck : =\((|Boolean|) $ !$)\#<vector 08eccc78>
 1>exit compiledLookupCheck : (#<compiled-function |EXPR;=;2$B;21|> . #<vector 08eccc78>)

after SPADCALL (it's not traced) "=" in EXPR trigger the bug:

  algEqual : ((0 . 0) 0 . 1)\((0 0 . 0) 0 1 . 0)\(|Expression| (|Float|))
             ^^^^^^^^^^^^^^^

I think above is not of type EXPR FLOAT.

Other thing:

1.0::UnivariatePuiseuxSeries(Expression Float,x,0.0)

(4)

Memory damaged if it's added to .axiom.input

See also:

#132

Series expansion with complex doesn't print expansion point in type expression

#136

Coercion of power series

Idem

bug #10063 (project axiom)

Possible information about this bug:
http://lists.gnu.org/archive/html/axiom-developer/2004-11/msg00137.html

Status: open => fixed somewhere

Status: fixed somewhere => closed