Travis CI build expects protobuf 2.6.0 but has 2.4.1 only

[bwegge]

This seems to be caused by an update of the protobuf-c library...

Build log:

checking pkg-config is at least version 0.9.0... yes
checking for protobuf... no
configure: error: Package requirements (protobuf >= 2.6.0) were not met:
Requested 'protobuf >= 2.6.0' but version of Protocol Buffers is 2.4.1
Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.
Alternatively, you may set the environment variables protobuf_CFLAGS
and protobuf_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
The command "git clone https://github.com/protobuf-c/protobuf-c.git && cd protobuf-c && ./autogen.sh && ./configure && make && sudo make install" failed and exited with 1 during .
Your build has been stopped.

[thomasquintana]

You have an outdated version of protocol buffers. Try installing from source https://github.com/google/protobuf/releases/download/v2.6.1/protobuf-2.6.1.tar.gz