SwiftGlibc tests failing on Haiku

Hello swift-dev,

I've recently been working on porting Swift to Haiku (started with 3.1
and now recently rebased
my patches to port Swift 4) and I'm currently at the point where I can
run the test suite. However,
after running these normal tests under Haiku, some of them which use the
Glibc modules keep failing
with messages such as 'Could not load Objective-C module SwiftGlibc'
with another message indicating
about missing headers.

I believe that something similar like this occurred in the FreeBSD
stdlibUnittest port [0] but this solution
seems to be very outdated. What would be the preferred way to solve this
issue in order to add support
for running tests on other platforms such as Haiku? I've attached a log
[1] of the tests that display the above
error message.

Joseph Hill

[1] https://gist.github.com/return/2dbcde9c5758303b3c4b460e1334d48