Segfault on some URLs

[josswright]

I'm not sure if this is a problem with the R package or the underlying library.

For some URLs, detect_language (and detect_language_multi) consistently cause a segfault.

> detect_language( url( "http://thehill.com" ), plain_text=FALSE )

 *** caught segfault ***
address 0x7f4dc86b66a4, cause 'invalid permissions'

Traceback:
 1: detect_language_cc(as_string(text), plain_text, lang_code)
 2: detect_language(url("http://thehill.com"), plain_text = FALSE)

I also get this error on http://qq.com.

Platform details:
R version 3.5.0 (2018-04-23) -- "Joy in Playing"
Copyright (C) 2018 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

Running under Arch Linux, and the most recent cld2 installed via devtools.