README.md: Add note about compilation of C tests.

diff --git a/README.md b/README.md
index 50a35fe33666a27a03ca45bb1be62ca335a00eaa..48fc715c22b3811eb089347444a60ec4c74d79d7 100644 (file)
--- a/README.md
+++ b/README.md
@@ -70,6 +70,8 @@ Note: For a verbose output of testing use: ``make ARGS="-V" test``
 
     build/tests/run_gtester.sh
 
+Note: The C tests have to be builded by ``make tests``)!
+
 ### Run only Python unittests (from your checkout dir):
 
     PYTHONPATH=`readlink -f ./build/src/python/` nosetests -s tests/python/tests/