Comment 14 for bug 1348384

The "vanilla" libspectre-0.2.7 doesn't show this behavior. The patch we are takling about has been introduced in the master branch of the git repository last June, but was reverted in September:
http://cgit.freedesktop.org/libspectre

Some time between those two dates, somebody added this patch to the debian/ubuntu version of libspectre though, and it has not yet been reverted here.

While this gets fixed, you can get the source of the debian package, download the vanilla libspectre, and build yourself a new .deb package without this faulty patch (make sure that the source repositories are enabled). I give below a script that should do this for you. There may be a better way, but at least this one works.

# Install the tools needed to build debian packages
sudo apt-get install devscripts
# Install the dependencies of libspectre
sudo apt-get build-dep libspectre1

# Make yourself a temporary directory
mkdir ~/tmp/
cd ~/tmp/

# Download the vanilla libspectre-0.2.7
wget http://libspectre.freedesktop.org/releases/libspectre-0.2.7.tar.gz

# Download the debian source code
sudo apt-get source libspectre1

# Create a new directory with the correct code
cd libspectre-0.2.7
uupdate ../libspectre-0.2.7.tar.gz -v 0.2.7-vanilla
cd ../libspectre-0.2.7-vanilla

# Remove the debian patch
rm debian/patches/*

# Build the package
dpkg-buildpackage -us -uc -nc
# Note: fore some reason, this fails to build libspectre-dev, but we don't care

# Install it
cd ../
sudo dpkg -i libspectre1_0.2.7-vanilla*.deb