[Pkg-owncloud-maintainers] Bug#803669: Breaks QProcess in owncloud-client tests on mips an mipsel

[Gaudenz Steinlin]

Source: qtbase-opensource-src
Version: 5.5.0+dfsg-3
Severity: serious

Setting the severity of this bug to serious because it causes another package 
to fail to build from source.

This version of Qt breaks the tests of owncloud-sync on mips and mipsel. Test also break
when compiling version 2.0.0+dfsg-1 of owncloud-client which previously
successfully built against the newer version of Qt. So I suspect this is
a bug in Qt and not in owncloud-client.

See here for the failing build logs:
https://buildd.debian.org/status/fetch.php?pkg=owncloud-client&arch=mipsel&ver=2.0.2%2Bdfsg-1&stamp=1445685652

I tried to debug this on the mipsel porter box but could not resovlve
the problem. This is what I found out:

- The problem is also present when running the tests with Qt
  5.5.0+dfsg-3 so setting this version. This is the first version of Qt
  5.5 available for mipsel. This is likely a bug introduced with Qt 5.5.

- This is the problematic part of the code in owncloud-client which
  triggers the bug (see test/testfilesystem.h in owncloud-client):
  https://anonscm.debian.org/cgit/pkg-owncloud/owncloud-client.git/tree/test/testfilesystem.h

 26     QByteArray shellSum( const QByteArray& cmd, const QString& file )
 27     {
 28        QProcess md5;
 29        QStringList args;
 30        args.append(file);
 31        md5.start(cmd, args);
 32        QByteArray sumShell;
 33        qDebug() << "File: "<< file;
 34 
 35        if( md5.waitForFinished()  ) {
 36 
 37          sumShell = md5.readAll();
 38          sumShell = sumShell.left( sumShell.indexOf(' '));
 39        }
 40        return sumShell;
 41     }

  This is called twice during the test to compute a md5/sha1 sum with the command 
  line tool to compare this against owncloud-clients internal implementation. The 
  test then fails because this function returns an empty string instead of the 
  correct result.

- Running the test under strace shows that the md5sum/sha1sum call succeeds and returns
  the correct string. But apparently waitForFinished just hangs for 30s (default timeout
  value) and then returns an error.

At this point I'm out of ideas on how to further debug this. Help by Qt maintainers or 
mips porters would be appreciated.

Gaudenz


-- System Information:
Debian Release: stretch/sid
  APT prefers testing-proposed-updates
  APT policy: (500, 'testing-proposed-updates'), (500, 'testing'), (100, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.2.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages libqt5core5a depends on:
ii  libc6         2.19-22
ii  libgcc1       1:5.2.1-22
ii  libglib2.0-0  2.46.1-1
ii  libicu55      55.1-5
ii  libpcre16-3   2:8.35-7.2
ii  libstdc++6    5.2.1-22
ii  zlib1g        1:1.2.8.dfsg-2+b1

Versions of packages libqt5core5a recommends:
ii  qttranslations5-l10n  5.5.1-2

Versions of packages libqt5core5a suggests:
ii  libthai0  0.1.22-2

-- no debconf information