Bug#777684: gnuplot-qt: with fvwm, qt window resize flickers and sometimes fails

[Vincent Lefevre]

Package: gnuplot-qt
Version: 4.6.6-2
Severity: normal

After running

gnuplot4 <<EOF
plot '-' using 1:2 t '' with line
0 0
10 10
e
pause mouse close
print "Done"
EOF

a window appears, but when I try to resize it, it flickers for a
fraction of second (i.e. the window is displayed several times with
several sizes), and when I release the mouse button, the final size
is not always the chosen one. More precisely, the different sizes
seem to be the sizes that occur during the resize operation. So,
to reproduce the bug, it is best to press the mouse button on a
resize corner, move the mouse a lot, then release the mouse button.

I think that this is a regression.

Note: I'm using fvwm with opaque resize:

  Style "*" ResizeOpaque

-- System Information:
Debian Release: 8.0
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.16.0-4-amd64 (SMP w/8 CPU cores)
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages gnuplot-qt depends on:
ii  gnuplot-data         4.6.6-2
ii  libc6                2.19-15
ii  libcairo2            1.14.0-2.1
ii  libedit2             3.1-20140620-2
ii  libgcc1              1:4.9.2-10
ii  libgd3               2.1.0-5
ii  libglib2.0-0         2.42.1-1
ii  liblua5.1-0          5.1.5-7.1
ii  libpango-1.0-0       1.36.8-3
ii  libpangocairo-1.0-0  1.36.8-3
ii  libqt4-network       4:4.8.6+git64-g5dc8b2b+dfsg-2+b1
ii  libqt4-svg           4:4.8.6+git64-g5dc8b2b+dfsg-2+b1
ii  libqtcore4           4:4.8.6+git64-g5dc8b2b+dfsg-2+b1
ii  libqtgui4            4:4.8.6+git64-g5dc8b2b+dfsg-2+b1
ii  libstdc++6           4.9.2-10
ii  libx11-6             2:1.6.2-3

gnuplot-qt recommends no packages.

Versions of packages gnuplot-qt suggests:
ii  gnuplot-doc  4.6.6-2

-- no debconf information