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From: Rusty Russell <rusty@rustcorp.com.au>
To: Hajime Tazaki <tazaki@sfc.wide.ad.jp>, richard@nod.at
Cc: linux-arch@vger.kernel.org, arnd@arndb.de, corbet@lwn.net, cl@linux.com,
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Subject: Re: [RFC PATCH 00/11] an introduction of library operating system for Linux (LibOS)
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Date: Wed, 01 Apr 2015 11:59:39 +1030
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Hajime Tazaki <tazaki@sfc.wide.ad.jp> writes:
> the issue here is the decision between 'no-ops' and
> 'assert(false)' depends on the context. an auto-generated
> mechanism needs some hand-written parameters I think.

Yes, I used auto-generated (fprintf, abort) stubs for similar testing in
pettycoin, where if it failed to link it would generate such stubs
for undefined symbols.

It's not a panacea, but it helps speed up rejiggin after code changes.
Generating noop stubs can actually make that process slower, as you can
get failures because you now need to do something in that stub.

> one more concern on the out-of-arch-tree design is that how
> to handle our asm-generic-based header files
> (arch/lib/include/asm). we have been heavily used
> 'generic-y' in the Kbuild file to reuse header files.

Yeah, the arch trick is clever.

Cheers,
Rusty.