This is a bug; here is a related example:
(%i1) dpart(sin(a+b),1);
Maxima encountered a Lisp error:
If you could file a bug report, please do.
--Barton
-----maxima-bounces at math.utexas.edu wrote: -----
>To:?maxima at math.utexas.edu
>From:?Alejandro?Morales?<mori at fis.unam.mx>
>Sent?by:?maxima-bounces at math.utexas.edu
>Date:?06/04/2010?08:29PM
>Subject:?[Maxima]?Lisp?stack?overflow
>
>Hi:
>With?the?following?commands?on?Maxima?I?get?a?Lisp?stack?overflow:
>r1:d/(c^2+d^2)^(1/2);
>r2:c/(c^2+d^2)^(1/2);
>r3:r1*cos(a)+r2*sin(a);
>r4:ratsimp(r3);
>r5:substpart((sqrt(d**2+c**2))*sin(a+b),r4,1);
>dpart(r5,1);
>***?-?Lisp?stack?overflow.?RESET
>[../src/eval.d:527]?reset()?found?no?driver?frame?
>(sp=0xb1c00c20-0xb1bfa760)
>Exiting?on?signal?6
>Process?maxima?aborted
>Is?there?some?mistake?
>Thanks:?Morales.
>
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