plot bug in linux



Alright as an end user I find it frustrating/traumatic that such errors
are to be expected.  I have recompiled the latest Maxima with GCL and
removed the Maxima I compiled with CLISP.  My question is, was there any
way of expecting this error in CLISP or is it a complete fluke?  

It seems so haphazard simplifying a simple trig. function and upon
converting it to a float an error is produced, not just any error but an
egregious one - this is somewhat traumatic as how can expect to use
Maxima for any major programming let alone as a calculator?  

Please any words from programmers, and end users would be appreciated.