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Re: PIC is wasteful
When a shared object is shared between two processes, there will be two
instances of the writable data sections, but both mapped to the same
logical address, as I understand it.
If I compile a shared object with -fno-pic in 32-bit x86 there will be
absolute addresses in the code section needing relocation. What happens
if this library is shared between two processes? Will I get two
instances of the code section, or will the system recognize that these
relocated references are identical in all processes because they refer
to data sections that are all mapped to the same logical address?
In 64 bit mode, I have to compile with -fpie which makes relative
addresses in the code section. All absolute references are in data
sections and exception handler tables, so I guess there is no issue here.