In member function webrtc::AudioDeviceLinuxPulse::KeyPressed(), szKey is uninitialized when USE_X11 is not #defined. This -Wuninitialized warning is not in webrtc.org's upstream repo [1]. It is a regression from bug 943353, which added USE_X11 #ifdefs. media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_pulse_linux.cc: In member function 'bool webrtc::AudioDeviceLinuxPulse::KeyPressed() const': media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_pulse_linux.cc:3132:52: error: '#'target_mem_ref' not supported by dump_expr#<expression error>' is used uninitialized in this function [-Werror=uninitialized] media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_pulse_linux.cc:3118:8: note: 'szKey' was declared here [1] https://code.google.com/p/webrtc/source/browse/trunk/webrtc/modules/audio_device/linux/audio_device_pulse_linux.cc#3033

I found this warning when trying to enable -Werror=uninitialized for all of mozilla-central in bug 1001975.

audio_device_alsa_linux.cc has the same -Wuninitialized warning: media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_alsa_linux.cc: In member function 'bool webrtc::AudioDeviceLinuxALSA::KeyPressed() const': media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_alsa_linux.cc:2387:52: error: '#'target_mem_ref' not supported by dump_expr#<expression error>' is used uninitialized in this function [-Werror=uninitialized] media/webrtc/trunk/webrtc/modules/audio_device/linux/audio_device_alsa_linux.cc:2373:8: note: 'szKey' was declared here

Bug 1001975 patched these upstream webrtc files to compile on Linux without X11, but it also removed the initialization of local variable szKey.