It's me again. Sorry for the double post.

zig test filename.zig on the following code produces a segfault on the second test.

const std = @import("std");
const allocator = std.heap.page_allocator;
var random = std.rand.DefaultPrng.init(142857).random;

fn alloc(comptime T: type, sz: usize) []T {
    const mem = allocator.alloc(T, sz) catch unreachable;
    return mem;
}
fn free(address: anytype) void {
    allocator.free(address);
}

test "no segfault without random.float" {
    // const x1 = random.float(f64);
    var thing = alloc(f64, 8);
    free(thing);
}

test "no segfault without alloc and free" {
    const x1 = random.float(f64);
    // var thing = alloc(f64, 8);
    // free(thing);
}

test "segfault when used together" {
    const x1 = random.float(f64);
    var thing = alloc(f64, 8);
    free(thing);
}

Here is the output:

$ zig test filename.zig 
Test [3/3] test "segfault when used together"... Segmentation fault at address 0x0
error: the following test command crashed:
zig-cache/o/43f68cfee589a095c17e125098f6a93c/test

It almost surely has to do with the ugly alloc() and free() things I made - I know some C but I'm by no means an expert, and was looking for some familiarity. The segfault dissappears if I call allocator.alloc or allocator.free directly.

I am however baffled at the fact that the x1 line interferes with the rest.

What is even happening here?