#3144 stackoverflow in integral

[kcrisman]

Maxima 5.36.1 http://maxima.sourceforge.net
using Lisp SBCL 1.2.11-1.fc22
(%i1) integrate(sin(k*x)/x*erf(x^2),x,0,inf);
Maxima encountered a Lisp error:
Control stack exhausted (no more space for function call frames).

See http://trac.sagemath.org/ticket/20467 as well as http://ask.sagemath.org/question/33144/unable-to-make-sense-of-maxima-expression-as-result-of-integration/ which has a different error which however I couldn't track down and may be unrelated to Maxima.

[Robert Dodier]

This seems to be a mistaken recursion in PTIMES%E which wants to call POLFACTORS to split up an expression and then try again on the result. But if POLFACTORS can't actually factor it, PTIMES%E is called again with the same argument, leading to a stack overflow.

I think I have a bug fix to prevent the stack overflow, although it doesn't help Maxima find the integral. Stay tuned.

[Robert Dodier]

Fixed by commit 4568937. Closing this report.

With this bug fix, Maxima can't find the integral, but at least it just returns a noun expression, instead of crashing.