When attempting to use the latest appcompat-v7 support library in my project, I get the following error:
/Users/greg/dev/mobile/android_project/app/build/int
After creating a second project in the workspace in eclipse, I had this problem. I believe it is because I created it with a different SDK version and this ovewrote the android-support-v7-appcompat library.
I tried to clean everything up but to no avail. Ultimately, the suggestion above to edit project.properties and change target=android-21 and set my project to Android 5.0, fixed it.