This program causes a segfault about 30-50% of the times it is run, on Windows 32 bit dmd 2.059head:


Compile with:
dmd -property -g -wi test.d


import std.stdio, std.algorithm, std.random;
void main() {
    immutable digits = "0123456789";
    enum nLoops = 5_000_000;
    enum maxLen = 20;
    char[maxLen] items;
    auto rnd = Xorshift();
    rnd.seed(0);
    foreach (i; 0 .. nLoops) {
        immutable len = uniform(0, maxLen, rnd);
        foreach (j; 0 .. len)
            items[j] = digits[uniform(0, digits.length, rnd)];
        string ns = items[0 .. len].idup;
        ns = cast(string)(cast(ubyte[])ns.dup).sort().release();
    }
}


The stack trace:


object.Error: Access Violation
----------------
...\dmd2\src\phobos\std\algorithm.d(7283): bool std.algorithm.__T8isSortedS593std10functional31__T9binaryFunVAyaa5_61203c2062Z9binaryFunTAhZ.isSorted(ubyte[])
...\dmd2\src\phobos\std\algorithm.d(6744): D3std9algorithm60__T4sortVAyaa5_61203cÙ62VE€Ž«12SwapStrategy0TAhZ€…¹F€ƒ‰S€„«5range37€ƒÒ11S€ƒšedR€„’€ƒª€‘ÝZ€¢
...\test.d(14): _Dmain
----------------


The bug disappears if you remove ".sort().release()".


Maybe it doesn't crash wi ldc2 linux 64, dmd-front-end 2.058 (I don't know what compilation switches).