I am referring to Lapack++ 2.5.4:
In LaQRLinearSolveIP is a call to the Fortran function dgels. According to  the passed info-value can be 0 (which does not have to be handled), +1 or -1.
The info-value is checked in the following way:
if (info < 0)
throw(LaException(fname, "Internal error in LAPACK: SGELS()"));
On one hand the exception string is wrong (it should at least mean "Internal error in LAPACK: DGELS()") and on the other hand, info > 0 is not checked.
If I am right, it is not possible for the user to check if LaQRLinearSolveIP returned a correct solution of the system.