Fix build with Emscripten/WASM

[tronical]

PCRE does not support Just-in-time compilation when targeting
WebAssembly.

[cbezault]

Cool, I assume then that you're a user of a custom Emscripten toolchain/triplet?

[tronical]

Yes, I’m using a custom triplet. Upstream emacripten / cmake use “Emscripten” as System name.

…

On Wed 28. Aug 2019 at 19:13, Curtis J Bezault ***@***.***> wrote: Cool, I assume then that you're a user of a custom Emscripten toolchain/triplet? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#7948?email_source=notifications&email_token=AAAALTQGWJ5BOXTADOY26L3QG2W3ZA5CNFSM4IRNA33KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD5L2LEA#issuecomment-525837712>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAALTQWYYG4XTVJN5AZTS3QG2W3ZANCNFSM4IRNA33A> .

[dan-shaw]

Thanks for the PR!