pi_piper with gtk aborts ruby interpreter (RPi Raspbian Stretch)

[xetum]

program:

require 'gtk3'
require 'pi_piper'

win = Gtk::Window.new
win.window_position = :center
win.border_width = 5

win.signal_connect("destroy") { Gtk.main_quit }

pin = PiPiper::Pin.new(pin: 24, direction: :out)

win.show_all
Gtk.main

aborts with:

/var/lib/gems/2.3.0/gems/pi_piper-2.0.0/lib/pi_piper/platform.rb:11: [BUG] Segmentation fault at 0xe92d000e
ruby 2.3.3p222 (2016-11-21) [arm-linux-gnueabihf]

-- Control frame information -----------------------------------------------
c:0006 p:---- s:0020 e:000019 CFUNC  :init
c:0005 p:0031 s:0017 e:000016 METHOD /var/lib/gems/2.3.0/gems/pi_piper-2.0.0/lib/pi_piper/platform.rb:11
c:0004 p:0254 s:0014 e:000013 METHOD /var/lib/gems/2.3.0/gems/pi_piper-2.0.0/lib/pi_piper/pin.rb:56 [FINISH]
c:0003 p:---- s:0010 e:000009 CFUNC  :new
c:0002 p:0083 s:0006 E:001330 EVAL   test_gtk.rb:12 [FINISH]
c:0001 p:0000 s:0002 E:000578 (none) [FINISH]

Tested on RPi 3B+ Raspbian Stretch. Works well on RPi 3B Raspbian Jessie

Any pointers?

[xetum]

[NOTE: this issue has been solved, pleaselook at the end]

ok, I was doing some testing...
Program is three lines:

require 'gtk3'
require 'pi_piper/bcm2835'
PiPiper::Bcm2835.init

program versions:

ruby 2.3.3p222 (2016-11-21) [arm-linux-gnueabihf]
gtk3-3.3.0 gem
pi_piper-2.0.0 gem (with libbcm2835 1.49 library, see https://github.com/zsyed91/pi_piper)

hardware:

RPi 3B+ Raspbian Stretch

comments:

-This same program works well on RPi 3B (no plus) Raspbian Jessie

• if I comment require 'gtk3' it works
• if I comment PiPiper::Bcm2835.init it works

---

segfault log:

test_gtk.rb:15: [BUG] Segmentation fault at 0xe92d000e
ruby 2.3.3p222 (2016-11-21) [arm-linux-gnueabihf]

-- Control frame information -----------------------------------------------
c:0003 p:---- s:0007 e:000006 CFUNC :init
c:0002 p:0032 s:0004 E:001c70 EVAL test_gtk.rb:15 [FINISH]
c:0001 p:0000 s:0002 E:001420 (none) [FINISH]

-- Ruby level backtrace information ----------------------------------------
test_gtk.rb:15:in <main>' test_gtk.rb:15:in init'

-- Other runtime information -----------------------------------------------

• Loaded script: test_gtk.rb

• Loaded features:

  0 enumerator.so
  1 thread.rb
  2 rational.so
  3 complex.so
  4 /usr/lib/arm-linux-gnueabihf/ruby/2.3.0/enc/encdb.so
  5 /usr/lib/arm-linux-gnueabihf/ruby/2.3.0/enc/trans/transdb.so
  6 /usr/lib/ruby/2.3.0/unicode_normalize.rb
  7 /usr/lib/arm-linux-gnueabihf/ruby/2.3.0/rbconfig.rb
  ...
  143 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/callback.rb
  144 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/io.rb
  145 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/autopointer.rb
  146 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/variadic.rb
  147 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/enum.rb
  148 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi/ffi.rb
  149 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi.rb
  150 /var/lib/gems/2.3.0/gems/pi_piper-2.0.0/lib/pi_piper/bcm2835.rb

• Process memory map:

00010000-00011000 r-xp 00000000 b3:02 147846 /usr/bin/ruby2.3
00020000-00021000 r--p 00000000 b3:02 147846 /usr/bin/ruby2.3
00021000-00022000 rw-p 00001000 b3:02 147846 /usr/bin/ruby2.3
01303000-01c01000 rw-p 00000000 00:00 0 [heap]
74fa1000-74fbe000 r-xp 00000000 b3:02 265396 /var/lib/gems/2.3.0/gems/ffi-1.9.25/lib/ffi_c.so
...
76f1b000-76f1c000 rw-p 00021000 b3:02 395 /lib/arm-linux-gnueabihf/ld-2.24.so
7e5c0000-7edbf000 rw-p 00000000 00:00 0 [stack]
7ef03000-7ef04000 r-xp 00000000 00:00 0 [sigpage]
7ef04000-7ef05000 r--p 00000000 00:00 0 [vvar]
7ef05000-7ef06000 r-xp 00000000 00:00 0 [vdso]
ffff0000-ffff1000 r-xp 00000000 00:00 0 [vectors]

[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html

---

[SOLVED]
In the end I've found the culprit...: neither gtk3, nor pi_piper..., but ruby interpreter ruby 2.3.3p222 (2016-11-21) [arm-linux-gnueabihf]

This is unfortunate because this ruby version is the one which gets installed with sudo apt-get install ruby on RPi Raspbian Stretch. Notice that Raspbian Jessie installs ruby 2.1 and the bug doesn't appear

Conclusion: using rvm with ruby 2.5 should be strongly recommended. You can close the ticket. Thanks for your attention