defint or sqrt bug?



quad_qags can do numerical (definite) integral,
but  integrate returns an error:
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Maxima 5.25.1 http://maxima.sourceforge.net
using Lisp GNU Common Lisp (GCL) GCL 2.6.8 (a.k.a. GCL)


(%i1) fpprintprec:8$

(%i2) quad_qags (
             quad_qags (1+sin(5*x*y+y^2), y, -sqrt(1-x^2), sqrt(1-x^2))[1],
                 x, -1, 1);

(%o2) [3.4367789,1.51120227E-9,399,0]

(%i3) integrate (
              integrate (1+sin(5*x*y+y^2), y, -sqrt(1-x^2), sqrt(1-x^2)),
                   x, -1, 1);

defint: lower limit of integration must be real; found -sqrt(1-x^2)
 -- an error. To debug this try: debugmode(true);
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Is this a bug?

Ted Woollett