maximum sized integer literal (u65535) trips compiler (memory, CPU use explosion)

[weber-martin]

Zig Version

0.9.1

Steps to Reproduce

create the problematic file with these steps (sorry for including code to generate this, gh issue complains about too long body for this field)

$ cat bomb.zig

const assert = @import("std").debug.assert;

test "integer literals" {
    // reading this 65537 ("0b" + 65535 "1"s) bytes long literal trips the compiler ...
    const literal_maxbit_pattern: u65535 = 0bX;
    assert(literal_maxbit_pattern > 0);
}

$ ones=$(head -c 65535 /dev/zero | tr '\0' '1');
$ sed -i bomb.zig -e "s;X;$ones;"

open something where you can see CPU and memory use (e.g. xosview, top, whatever)
then run the test:
zig test bomb.zig
Watch the resource usage explode.

Expected Behavior

test runs successfully

Actual Behavior

test run runs out of memory

[weber-martin]

I believe this really has to do with consuming the literal; computing the same value via (wrapping) arithmetic works just fine:

    const maxbit: u65535 = 0;
    const maxbit_pattern = maxbit -% 1;
    assert(maxbit_pattern ^ 0 == maxbit_pattern);
    assert((maxbit_pattern - 1) & 1 == 0);
    assert((maxbit_pattern +% 1) & maxbit_pattern == 0);