* Laurent Cimon via Gcc: > I realize that compilers have evolved with time, and that many > things required the use of function prototypes, but my question is, > what is the historical reason that a function defined further down > in a C file cannot be used without a function prototype?
The most common implementation strategy in the 80s was not to read the entire source file into memory and process function definitions one function at a time. This favored forward declarations once prototypes were introduced, otherwise the existing compilers would have to change rather drastically to support this feature. Note that historic C allowed calling undeclared functions (as long as their return type was compatible with int). It had very little type checking, so a one-pass compiler implementation was still possible.
