Terminal app crashes with "Failed to load libGLESv2"

[Michał Sawicz]

Most likely due to [1] (checking), terminal app crashes on startup, printing:

> Failed to load libGLESv2

An example OOPS can be seen under [2].

[1] https://code.launchpad.net/~gerboland/qtubuntu/adopt-more-eglconvenience2/+merge/295248
[2] https://errors.ubuntu.com/oops/020da136-3673-11e6-9055-fa163eec78fa

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: qtubuntu-android 0.62+15.04.20160527.1-0ubuntu1
Uname: Linux 3.10.100-user-01767-gf5aa556-dirty aarch64
ApportVersion: 2.17.2-0ubuntu1.3touch1
Architecture: armhf
Date: Mon Jun 20 01:05:39 2016
InstallationDate: Installed on 2016-06-18 (1 days ago)
InstallationMedia: Ubuntu 15.04 - armhf (20160618-020304)
SourcePackage: qtubuntu
UpgradeStatus: No upgrade log present (probably fresh install)

[Michał Sawicz (saviq)]

I'm now eye-balling https://code.launchpad.net/~gerboland/qtubuntu/minor-cleanup/+merge/296420 as the culprit after all, confirming soon.

[Gerry Boland (gerboland)]

My eglconvenience branch does cause this, but annoyingly by doing the correct thing.

Before eglconvenience, we hardcoded GLESv2.0 into QtUbuntu. With eglconvenience, we query the GL version string and correctly fetch the GL version the driver supports. On several of our devices, that is actually GLESv3.0

If GLESv3 is available (not all devices have it), Qt tries to use it instead of alternative GLv2 calls (as they're usually better). It does this by creating a QOpenGLES3Helper class internally, when particular GL calls are made.

Most of our pure QML apps don't end up calling any of those particular GL calls, so work just fine. But Terminal app does.

QOpenGLES3Helper on creation uses QLibrary to load libGLESv2.so and resolve some symbols in it. This is failing for some reason, and prints the "Failed to load libGLESv2.so" message as a result. I suspect this fail has to do with lp:1490956

I've proposed lp:~gerboland/qtubuntu/disable-gles3-for-now as a workaround for this issue

[Launchpad Janitor (janitor)]

This bug was fixed in the package qtubuntu - 0.62+16.10.20160620-0ubuntu1

---------------
qtubuntu (0.62+16.10.20160620-0ubuntu1) yakkety; urgency=medium

  * Revert r324 "EGL convenience" (LP: #1594198)

 -- Michał Sawicz <email address hidden> Mon, 20 Jun 2016 08:49:40 +0000

[Gerry Boland (gerboland)]

Digging into the actual root cause, QOpenGLES3Helper has QLibrary load "libGLESv2.so" but this is failing. Using LD_DEBUG=libs you can see:

      5646: find library=libGLESv2.so [0]; searching
      5646: search path=/vendor/lib:/system/lib (LD_LIBRARY_PATH)
      5646: trying file=/vendor/lib/libGLESv2.so
      5646: trying file=/system/lib/libGLESv2.so
      5646: search cache=/etc/ld.so.cache
      5646: search path=/lib/arm-linux-gnueabihf:/usr/lib/arm-linux-gnueabihf/vfp:/usr/lib/arm-linux-gnueabihf:/lib/tls/v7l/neon/vfp:/lib/tls/v7l/neon:/lib/tls/v7l/vfp:/lib/tls/v7l:/lib/tls/neon/vfp:/lib/tls/neon:/lib/tls/vfp:/lib/tls:/lib/v7l/neon/vfp:/lib/v7l/neon:/lib/v7l/vfp:/lib/v7l:/lib/neon/vfp:/lib/neon:/lib/vfp:/lib:/usr/lib/tls/v7l/neon/vfp:/usr/lib/tls/v7l/neon:/usr/lib/tls/v7l/vfp:/usr/lib/tls/v7l:/usr/lib/tls/neon/vfp:/usr/lib/tls/neon:/usr/lib/tls/vfp:/usr/lib/tls:/usr/lib/v7l/neon/vfp:/usr/lib/v7l/neon:/usr/lib/v7l/vfp:/usr/lib/v7l:/usr/lib/neon/vfp:/usr/lib/neon:/usr/lib/vfp:/usr/lib (system search path)
and off it goes searching all those paths.

Problem is the library is actually called libGLESv2.so.2 on hybris. Qt isn't able to locate the file as a result. I don't know if the library should be called libGLESv2.so only for GLESv3, but if so, it would explain a lot.

For fun, I symlinked libGLESv2.so.2 to libGLESv2.so, for which I got this error:
"OpenGL ES 3.0 entry points not found"
which makes sense as hybris is only exporting GLESv2 symbols, and nothing from GLESv3 yet.

So my patch above is actually the best solution until hybris supports GLESv3.

[Gerry Boland (gerboland)]

https://github.com/libhybris/libhybris/pull/316 has a better solution to this issue for now

[Gerry Boland (gerboland)]

https://github.com/libhybris/libhybris/pull/316 has been landed. I can remove the QtUbuntu workaround