bug#35259: 27.0.50; Segmentation fault (xstrdup gdk_monitor_get_model)

[Jhair Tocancipa Triana]

Emacs crashes randomly, sometimes when clicking links in eww. The crash
is not easily reproducible, nevertheless the core dump points to a
segfault at xfns.c:

a35e06bbe27 (Alexander Gramiak   2019-04-06 5033)       mi->name = xstrdup 
(gdk_monitor_get_model (monitor));

gkd_monitor_get_model is returning NULL in my case causing the segfault
at xstrdup.

The gkd_monitor_get_model documentation says the function may return
NULL.

https://developer.gnome.org/gdk3/stable/GdkMonitor.html#gdk-monitor-get-model

Maybe we need to guard against a NULL return value.

Please find attached the bt full gdb output.

bt-full.log.gz
Description: application/gzip

In GNU Emacs 27.0.50 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.4)
 of 2019-04-13 built on DE1-JT-Ubuntu
Repository revision: f9694a713824d402bcba01064ac2f95156bf4161
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12001000
System Description: Ubuntu 18.10

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((conses 16 1834577 160000)
 (symbols 48 59886 108)
 (strings 32 689366 67654)
 (string-bytes 1 46468691)
 (vectors 16 242042)
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 (floats 8 421 280)
 (intervals 56 5401 887)
 (buffers 992 41))

-- 
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