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Storing the data in 18 independent variables is awkward. The naming of your variables suggests that each group of six doubles represents an object, which I've called a Sexdoublet.

Throwing all the code into main() is poor practice; there should be a function to do the importing. It should accept an istream parameter and return a vector of Sexdoublets.

I don't know what you were hoping to accomplish with if (!ifs) ifs >> trash; — if the ifstream is bad then you shouldn't try reading from it.

Hard-coding the filename is probably a bad idea. I've used the convention of reading from either a file that is specified on the command line, or from standard input otherwise.

#include <fstream>
#include <iostream>
#include <string.h>
#include <vector>

/* A struct of six doubles */
struct Sexdoublet {
    double x, y, d, m, c, t;

    friend std::istream &operator>>(std::istream &in, Sexdoublet &r) {
        return in >> r.x >> r.y >> r.d >> r.m >> r.c >> r.t;
    }

    friend std::ostream &operator<<(std::ostream &out, const Sexdoublet &r) {
        return out << "[ x = " << r.x
                   << ", y = " << r.y
                   << ", d = " << r.d
                   << ", m = " << r.m
                   << ", c = " << r.c
                   << ", t = " << r.t << " ]";
    }
};

std::vector<Sexdoublet> import(std::istream &in) {
    std::vector<Sexdoublet> data;
    Sexdoublet s;
    while (in >> s) {
        data.push_back(s);
    }
    return data;
}

int main(int argc, char *argv[]) {
    // If the first command-line argument is not "-", treat it as the filename
    // from which to read the input.  Otherwise, read from STDIN.
    const char *filename = (argc >= 2 && 0 != strcmp("-", argv[1])) ?
                                argv[1] : NULL;
    std::ifstream f;
    std::istream &in = filename ? (f.open(filename), f) : std::cin;
    if (!f) {
        std::cerr << "Error opening " << filename << ": "
                  << strerror(errno) << std::endl;
        return 1;
    }

    std::vector<Sexdoublet> data = import(in);
    std::for_each(data.begin(), data.end(), [](const Sexdoublet &s) {
        std::cout << s << std::endl;
    });
    return 0;
}