diff --git a/.travis.yml b/.travis.yml
index 59ef0053a..105ae8dd4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -47,7 +47,7 @@ script:
 # use same hack as for kernel to work around cppchecks broken exit status with -j 2 ; create file, tee everything to the file and stdout, grep for errors in the file
   - touch /tmp/cppcheck.cppcheck
   - ./cppcheck --error-exitcode=1 -Ilib --enable=style --suppressions-list=.travis_suppressions . -j 2 |& tee /tmp/cppcheck.cppcheck
-  - sh -c "! grep "^\[" /tmp/cppcheck.cppcheck"
+  - sh -c "! grep '^\[' /tmp/cppcheck.cppcheck"
   - cd ./gui
 # clean rebuild
   - git clean -dfx .