QGIS » QGIS Application

I'm getting this error trying to build qgis from the master branch:

sip: Unable to find file "QtCore/QtCoremod.sip"
make²: * [python/core/sip_corepart0.cpp] Error 1
make¹: * [python/CMakeFiles/python_module_qgis__core.dir/all] Error 2

Here's the cmake output:

-- QGIS version: 2.5.0 Master (20500)
-- Could not find GRASS
-- Found Proj: /usr/lib/libproj.so
-- Found GEOS: /usr/local/lib/libgeos_c.so (3.5.0)
-- Found GDAL: /usr/local/lib/libgdal.so (2.0.0dev)
-- Found Expat: /usr/lib/x86_64-linux-gnu/libexpat.so
-- Found Spatialindex: /usr/lib/x86_64-linux-gnu/libspatialindex.so
-- Found Qwt: /usr/lib/libqwt.so (6.0.0-svn)
-- Found Sqlite3: /usr/lib/x86_64-linux-gnu/libsqlite3.so
-- Found PostgreSQL: /home/postgresql-9.3.4/lib/libpq.so
-- Found SpatiaLite: /usr/lib/x86_64-linux-gnu/libspatialite.so
-- Found Qt version: 4.8.6
-- Touch support disabled
-- Found QScintilla2: /usr/lib/libqscintilla2.so (2.8.1)
-- Pedantic compiler settings enabled
-- Debug output enabled
-- Found Python executable: /usr/bin/python
-- Found Python version: 2.7.6
-- Found Python library: /usr/lib/x86_64-linux-gnu/libpython2.7.so
-- Found SIP version: 4.15.5
-- Found PyQt4 version: 4.10.4
-- Found QScintilla2 PyQt4 module: 2.8.1
-- Found GSL: L/usr/lib -lgsl -lgslcblas -lm
- Qsci sip file not found - disabling bindings for derived classes
-- Ctest Binary Directory set to: /usr/src/qgis/build/master/output/bin
-- Configuring done
-- Generating done
-- Build files have been written to: /usr/src/qgis/build/master