MinGW: std.math.{sin, tan} crash/garbage

[dnadlinger]

bearophile reported the following issue with the 0.11.0 MinGW32 build on dm.D.ldc:

———

Maybe I have found some more problems. The program:

import core.stdc.stdio, std.math;

void test(in double nLoops) nothrow {
    double rsin = 0.0;
    double rtan = 0.0;

    double i = 0.0;
    while (i < nLoops) {
        rsin = sin(i);
        rtan = tan(i);
        i++;
    }

    printf("i: %f\n", i);
    printf("sin: %f\n", rsin);
    printf("tan: %f\n", rtan);
}

void main() {
    test(2_000_000);
}

DMD seems to print the correct values:

i: 2000000.000000
sin: -0.989602
tan: 6.880292

The program compiled with ldmd2 (on a 32 bit Windows system, with no switches) crashes when it tries to print "i". If I comment out the printf line of "i" then the program prints:

sin: -0.000000
tan: nan

[dnadlinger]

This was also caused by the Win64-specific longdouble (i.e. real functions), and is fixed in Git master. (cc @bearophile)