Test runner causes undefined behaviour, segfault as null pointer

[slate glen]

Hey! I'm using the following test runner -> https://gist.github.com/karlseguin/c6bea5b35e4e8d26af6f81c22cb5d76b

the following test works perfectly fine, no segfault issues:

test "deinitialize db tests" {
    const db = @import("../db.zig");
    const dotenv = @import("../util/dotenv.zig").dotenv;
    const allocator = std.testing.allocator;

    var env = try dotenv.init(allocator, ".testing.env");
    defer env.deinit();
    ...
}

however what it does doesn't do is wait for the other tests to finish, which is why I decided to add tests:afterAll to the test name, which results in the following stack trace

Segmentation fault at address 0xffffffffffffffff
path\to\zig\std\mem\Allocator.zig:269:35: 0x7ff6ecc11044 in allocBytesWithAlignment__anon_19575 (test.exe.obj)
    const byte_ptr = self.rawAlloc(byte_count, .fromByteUnits(alignment), return_address) orelse return Error.OutOfMemory;
                                  ^
path\to\zig\std\mem\Allocator.zig:260:40: 0x7ff6ecbec8d1 in allocWithSizeAndAlignment__anon_9188 (test.exe.obj)
    return self.allocBytesWithAlignment(alignment, byte_count, return_address);
                                       ^
path\to\zig\std\mem\Allocator.zig:242:41: 0x7ff6ecc1f054 in alignedAlloc__anon_22612 (test.exe.obj)
    return self.allocAdvancedWithRetAddr(T, alignment, n, @returnAddress());
                                        ^
path\to\zig\std\array_list.zig:474:67: 0x7ff6ecc24636 in ensureTotalCapacityPrecise (test.exe.obj)
                const new_memory = try self.allocator.alignedAlloc(T, alignment, new_capacity);
                                                                  ^
path\to\zig\std\array_list.zig:66:48: 0x7ff6ecc0a0b2 in initCapacity (test.exe.obj)
            try self.ensureTotalCapacityPrecise(num);
                                               ^
path\to\zig\std\unicode.zig:1784:52: 0x7ff6ecbe60b8 in wtf16LeToWtf8Alloc (test.exe.obj)
    var result = try std.ArrayList(u8).initCapacity(allocator, wtf16le.len);
                                                   ^
path\to\zig\std\process.zig:303:55: 0x7ff6ecbc24b5 in getEnvMap (test.exe.obj)
            const key = try unicode.wtf16LeToWtf8Alloc(allocator, key_w);
                                                      ^
0x7ff6ecbc19b4 in init (test.exe.obj)
        var map = try std.process.getEnvMap(allocator);
                                           ^
0x7ff6ecf3f927 in test.deinitialize db tests:afterAll (test.exe.obj)
    var env = try dotenv.init(allocator, ".testing.env");

the dotenv struct looks like

pub const dotenv = struct {
    map: std.process.EnvMap = undefined,
    pub fn init(allocator: Allocator, filename: ?[]const u8) !dotenv {
        var map = try std.process.getEnvMap(allocator);
        ...
      return .{.map=map}
  }
  pub fn deinit(self: *dotenv) void {
        self.map.deinit();
    }

but i dont see why its really trying to use a null pointer upon initialization, only when the test is ran in afterAll mode

chanigng the allocator to smp_allocator has fixed it... but why? does this segment deinitialize every testing allocator everywhere and prevent future ones from being initialized?