"failed to find function _sbrk" when compiling with --llvm-lto 3 -s USE_PTHREADS -s FETCH=1

[VirtualTim]

Probably the same issue as #8242, however the _sbrk requirement is new.
This worked in 1.38.45, but broke in 1.38.46. I have only tested with the fastcomp backend.

I figured I'd log this as a separate issue, in case this is fresh in someone's mind (maybe caused by #9438?), but feel free to close as a dupe if you don't think this is right.

[kripken]

Looks like this is specific to fastcomp, I don't see an error using upstream.

[stale]

This issue has been automatically marked as stale because there has been no activity in the past year. It will be closed automatically if no further activity occurs in the next 30 days. Feel free to re-open at any time if this issue is still relevant.