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Re: why the difference of two global pointers is not a constant?
Rafael Espíndola writes:
> > because that is what the language standard says.
> > In general, the difference between two global pointers is something
> > known only to the linker -- too late to evaluate as constant
> > expression.
> In the particular case of two static functions or two static global
> pointers, it is possible for the compiler to compute it. Isn't it? I
> think that the linker will reorder the sections, but not the functions
> inside a section.
> The reason why I want to do this is to avoid relocations when a dso is
> loaded. Using the difference of two pointer I could build a constant
> table and add one of the pointers at runtime.
This isn't possible with global symbols in a DSO because some other
DSO (or indeed the exe) might also define one of the symbols.