Internal compiler error

[typeless]

use std

extern const __bss_start : void#

const main = {

        const fp = __bss_start
        for fp : (&__bss_start)[:1]
        ;;
}

Output:

Building
    6m -I /lib/myr in.myr
CRASH: 6m -I /lib/myr in.myr
Internal error: mbld: exited with status 1

I am playing around some unusual cases :trollface:

[oridb]

On Wed, 06 Dec 2017 06:07:00 +0000 (UTC), Mura Li notifications@github.com wrote:

use std

extern const __bss_start : void#

const main = {

        const fp = __bss_start
        for fp : (&__bss_start)[:1]
        ;;
}

Output:

Building
  6m -I /lib/myr in.myr
CRASH: 6m -I /lib/myr in.myr
Internal error: mbld: exited with status 1

I am playing around some unusual cases :trollface:

Yep, Generally I don't do that much with externs. The error message has been fixed.

-- Ori Bernstein

[typeless]

Ah, I should have made it clearer. The extern const declaration without initialization is expected, but the crash happens when the fp identifier is reused in the for loop as the iterator. It compiles when I change either one of the two fp identifiers to another name.

[oridb]

On Wed, 06 Dec 2017 07:32:29 +0000 (UTC), Mura Li notifications@github.com wrote:

Ah, I should have made it clearer. The extern const declaration without initialization is expected, but the crash happens when the fp identifier is reused in the for loop as the iterator. It compiles when I change either one of the two fp identifiers to another name.

Yes, that's by design. The for loop iterator is a pattern match, and you can match against constants.

For example:

const Foo = 123
const Bar = 234

for (Foo, x) in [(Foo, 1), (Bar, 2), (Baz, 3)][:]
    std.put("x={}\n")
;;

will print only the first value that matches Foo:

x=1

You can think of this form of loop as syntax for:

for pat in iterable
    /* loop body */
;;

for var i = 0; i < iter.len; i++
    match iter[i]
    | pat:
        /* loop body */
    | _:
        /* skip */
    ;;
;;

-- Ori Bernstein