RE: [PATCH] arm64: Remove AArch64 X30 redundant register alias
From: naohirot@fujitsu.com <hidden>
Date: 2021-07-15 01:31:25
Hi Robin, Marc, Thank you for your quick feedbacks!
From: Robin Murphy <robin.murphy@arm.com> Sent: Wednesday, July 14, 2021 8:39 PM
On 2021-07-14 10:54, Marc Zyngier wrote:quoted
On Tue, 13 Jul 2021 14:29:45 +0100, Naohiro Tamura [off-list ref] wrote:
quoted
quoted
-/* - * Register aliases. - */ -lr .req x30 // link register - /* * Vector entry */I seem to vaguely remember that this isn't always defined, see [1] for a recent example. Dropping it altogether may end-up being pretty disruptive.Right, the built-in alias was only introduced a few years ago in binutils 2.29 (where it initially caused problems itself by being a bit overzealous[2]), but our current minimum version is 2.23, so we still need this for older but still-supported toolchains (e.g. I expect the Linaro GCC 7-based releases with binutils 2.28 are still being used).
I confirmed that binutils 2.23 doesn't have the alias [3]. So I withdraw this patch. [3] https://sourceware.org/binutils/docs-2.23/as/AArch64-Directives.html#AArch64-Directives p.s. I have learned how to submit a patch 😊 Thanks. Naohiro _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel