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Date: Mon, 26 Sep 2011 12:33:38 +0100
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From: Peter Maydell <peter.maydell@linaro.org>
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Subject: Re: [Qemu-devel] [PATCH v2] tcg: Remove stack protection from
	helper functions
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, Laurent Desnogues <laurent.desnogues@gmail.com>, Anthony Liguori <aliguori@us.ibm.com>, Mulyadi Santosa <mulyadi.santosa@gmail.com>, qemu-devel <qemu-devel@nongnu.org>

On 26 September 2011 11:51, Jan Kiszka <jan.kiszka@siemens.com> wrote:
> This increases the overhead of frequently executed helpers. We need to
> move rule past QEMU_CFLAGS assignment to ensure that the required simple
> assignment picks up all bits. The signal workaround is moved just for
> the sake of consistency.

> +# NOTE: Must be after the last QEMU_CFLAGS assignment
> +op_helper.o user-exec.o: QEMU_CFLAGS := $(subst -fstack-protector-all,,$(QEMU_CFLAGS)) $(HELPER_CFLAGS)

Why also user-exec.o ? Why not the other source files with helpers in?
This doesn't seem very consistent. Maybe the right answer is to have
some of the offending helper functions inline instead? (Or to not
have -fstack-protector-all globally?)

-- PMM