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    SubjectRe: Unnecessary Relocation Hiding?
    Sorry for perhaps extending the specific question to a more generic
    one. In which cases shall we, in current or future development,
    prevent gcc from knowing a pointer-addition in the way RELOC_HIDE? And
    in what cases shall we just write pure C point addition?

    After all, we are writing an OS in C not in pure assembly, so I am
    just trying to learn some generial rules to mimize the raw assembly in
    development.

    Feng,Dong


    2006/8/25, Paul Mackerras <paulus@samba.org>:
    > Christoph Lameter writes:
    >
    > No, RELOC_HIDE came from ppc originally. The reason for it is that
    > gcc assumes that if you add something on to the address of a symbol,
    > the resulting address is still inside the bounds of the symbol, and do
    > optimizations based on that. The RELOC_HIDE macro is designed to
    > prevent gcc knowing that the resulting pointer is obtained by adding
    > an offset to the address of a symbol. As far as gcc knows, the
    > resulting pointer could point to anything.
    >
    > It has nothing to do with linker relocations.
    >
    > Paul.
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