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@(@\newcommand{\W}[1]{ \; #1 \; } \newcommand{\R}[1]{ {\rm #1} } \newcommand{\B}[1]{ {\bf #1} } \newcommand{\D}[2]{ \frac{\partial #1}{\partial #2} } \newcommand{\DD}[3]{ \frac{\partial^2 #1}{\partial #2 \partial #3} } \newcommand{\Dpow}[2]{ \frac{\partial^{#1}}{\partial {#2}^{#1}} } \newcommand{\dpow}[2]{ \frac{ {\rm d}^{#1}}{{\rm d}\, {#2}^{#1}} }@)@ This is cppad-20221105 documentation. Here is a link to its current documentation .
Abort Current Recording: Example and Test

# include <cppad/cppad.hpp>
# include <limits>

bool abort_recording(void)
{   bool ok = true;
    double eps = 10. * CppAD::numeric_limits<double>::epsilon();

    using CppAD::AD;

    try
    {   // domain space vector
        size_t n = 1;
        CPPAD_TESTVECTOR(AD<double>) x(n);
        x[0]     = 0.;

        // declare independent variables and start tape recording
        CppAD::Independent(x);

        // simulate an error during calculation of y and the execution
        // stream was aborted
        throw 1;
    }
    catch (int e)
    {   ok &= (e == 1);

        // do this in case throw occurred after the call to Independent
        // (for case above this is known, but in general it is unknown)
        AD<double>::abort_recording();
    }
    /*
    Now make sure that we can start another recording
    */

    // declare independent variables and start tape recording
    size_t n  = 1;
    double x0 = 0.5;
    CPPAD_TESTVECTOR(AD<double>) x(n);
    x[0]      = x0;
    CppAD::Independent(x);

    // range space vector
    size_t m = 1;
    CPPAD_TESTVECTOR(AD<double>) y(m);
    y[0] = 2 * x[0];

    // create f: x -> y and stop tape recording
    CppAD::ADFun<double> f(x, y);

    // forward computation of partials w.r.t. x[0]
    CPPAD_TESTVECTOR(double) dx(n);
    CPPAD_TESTVECTOR(double) dy(m);
    dx[0] = 1.;
    dy    = f.Forward(1, dx);
    ok   &= CppAD::NearEqual(dy[0], 2., eps, eps);

    return ok;
}
Input File: example/general/abort_recording.cpp