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SubjectRe: 2.3.26pre2 compile error


On Fri, 5 Nov 1999, Peter Samuelson wrote:

> [Jes Sorensen <Jes.Sorensen@cern.ch>]
> > > > Then you extract that single function from libgcc and put it in the
> > > > kernel instead of linking in the entire libgcc.a
> [Horst von Brand <vonbrand@inf.utfsm.cl>]
> > > That is ld(1)'s job.
> [Jes Sorensen]
> > Rubbish, the kernel should never get even close to functions provided
> > from outside the kernel source tree.
>
> What is the difference? `gcc' implements standard C. For some of the
> standard C requirements it relies on libc, for some it has its own ways
> of providing them. One such way is to generate assembler code from its
> parse trees, another is through linking to libgcc.a. Thus libgcc.a is
> in one sense not really a library so much as just part of the compiler.
>
> Horst is right. `ld' is very good at extracting a single object file
> out of a library, and libgcc.a is (like any good library) compiled one
> function per object file. Why do this work by hand?

Because in 99% of cases you don't _want_ those operations. Part of
standard or not, gcc on x86 makes them _slow_.


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