Linker command failed with exit code 1 error in Xcode project

Question

I was working on my project and suddenly after editing the code and compiling gave this error:

ld: warning: directory not found for option \'-
L/Use

Answer 1

In case this comes in useful for anyone else--I just had this same error, and turns out the cause was initializing a variable in my header file rather than in the main file.