Bug#1079077: mozjs128: Fails to build on armel

[Simon McVittie]

Control: tags -1 + upstream pending
Control: forwarded -1 https://bugzilla.mozilla.org/show_bug.cgi?id=1915578

On Mon, 19 Aug 2024 at 16:51:35 -0400, Jeremy Bícha wrote:
> I attempted a very simple -latomic fix but it failed. mozjs has a more
> complicated buildsystem so maybe I didn't set it in the right place.

Adding -latomic to LDFLAGS will not usually work, because order matters:
if there are atomic operations in a static library, then the link line
needs to include "my-static-library.a -latomic" in that order. LDFLAGS
normally appear before all libraries, though.

The bug was that the build system tried to detect whether atomic operations
require -latomic, but due to a build system mistake it was actually
detecting whether atomic operations require ["-","l","a","t","o","m","i","c"]
which of course doesn't actually help.

After fixing this, there are still several test failures because the
SharedArrayBuffer feature is disabled, but I think it's better if we treat
those as a separate armel bug.

    smcv