[coreboot] Time for a new project

Segher Boessenkool segher at kernel.crashing.org
Sun Apr 13 00:59:54 CEST 2008

> Some Linux kernel verification mechanisms have caught compiler bugs in
> the past. That's why I considered the possibility to do this as well.

The only ones that I am aware of are *generic* sanity checks in the
kernel, that manage to trip on something that turned out to be a 
bug.  Adding specific sanity checks for every piece of code that only
checks for compiler bugs is foolishness (hint: it's impossible to ever
get even 1% cover; and that check code itself is run through that same
compiler anyway!)

If there is a *specific* compiler bug that you are aware of, it is
nicer to catch it at build time, if possible, or just refuse to build
with the broken compiler.

>> At some point the entry point to a blob was at the beginning of the
>> file. Adding the flexibility to begin with moved complexity from
>> compile time to run time -- guess what, that was a bad idea.
> Unless you fork gcc, having the entry point at the beginning of initram
> is not possible. It worked by accident in the past and I'm pretty sure
> Segher will confirm that we can't rely on that.

No, I confirm you *can* rely on that: just set up your linker script
and your crt.o so this works.  Something like

         .start : { crt0.o(*) }
         .text : { *(.text) }
         .data : { *(.data) }

will guarantee that all of crt0 ends up before anything else (and there
is no need to make it a separate section, FWIW).


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