C++ (gcc), 143 bytes
Explanation: it uses the constructor of a class to do the Fibonacci increment operation, and then sets up a variable number of global instances of that class to be initialized before main. The catch being that all those variables have to be named differently, and there's a bit of preprocessor magic needed to get the __LINE__ macro combined into the variable names.
(And then, since I couldn't see any way to be able to do a #include before the line which had to be commented in all occurrences but one, it ended up being a bit expensive to manually define a close-enough printf prototype.)
int m,n=1;struct A{A(){m+=n;n=m-n;}};extern"C" int printf(...);int main(){printf("%d",m);}
#define Y(x) A a##x;
#define X(x) Y(x)
X(__LINE__)//
Daniel Schepler
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