diff --git a/.travis.yml b/.travis.yml
index 558c96bbe..f722a5fb3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,11 +12,9 @@ env:
 
 before_install:
     - brew update 1>/dev/null
-    - brew install doxygen nasm gettext yasm optipng imagemagick coreutils intltool ninja
-    - brew outdated cmake || brew upgrade cmake
-    - brew link gettext --force
     - brew tap Gui13/linphone
-    - brew install antlr3.2
+    - brew install doxygen nasm yasm optipng imagemagick coreutils intltool ninj antlr3.2
+    - brew upgrade cmake
     - wget --no-check-certificate https://raw.github.com/yuvi/gas-preprocessor/master/gas-preprocessor.pl
     - chmod +x gas-preprocessor.pl
     - sudo mv gas-preprocessor.pl /usr/local/bin
diff --git a/prepare.py b/prepare.py
index 88a319a45..da6508e09 100755
--- a/prepare.py
+++ b/prepare.py
@@ -168,7 +168,7 @@ def check_tools():
         print("Invalid location: linphone-iphone path should not contain any spaces.")
         ret = 1
 
-    for prog in ["autoconf", "automake", "pkg-config", "doxygen", "java", "nasm", "gettext", "wget", "yasm", "optipng"]:
+    for prog in ["autoconf", "automake", "pkg-config", "doxygen", "java", "nasm", "cmake", "wget", "yasm", "optipng"]:
         ret |= check_installed(prog, "it")
     ret |= check_installed("ginstall", "coreutils")
     ret |= check_installed("intltoolize", "intltool")
@@ -492,6 +492,8 @@ def main(argv=None):
     selected_platforms = list(set(selected_platforms))
 
     if args.G__generator == 'Ninja':
+        if check_installed("ninja", "it") != 0:
+            return 1
         generator = 'ninja -C'
     else:
         generator = '$(MAKE) -C'