Build throwing error "Command ... llvm-gcc-4.2 failed with exit code 1"

Here's the log from the build. This is a brand new project in Xcode 4, so the only non-regular things in it are as follows:

1. A .c file
2. A .a library
3. A bunch of header files

I've been playing with the build settings and searching for answers for a couple of hours now to see if it would go away, but it didn't. Any help you have would be appreciated.!

The output (click for a larger image):