Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753000AbbBXFTi (ORCPT ); Tue, 24 Feb 2015 00:19:38 -0500 Received: from mail-we0-f172.google.com ([74.125.82.172]:41995 "EHLO mail-we0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752922AbbBXFTc (ORCPT ); Tue, 24 Feb 2015 00:19:32 -0500 MIME-Version: 1.0 In-Reply-To: <20150223132736.GH32737@e104818-lin.cambridge.arm.com> References: <20150223132736.GH32737@e104818-lin.cambridge.arm.com> Date: Tue, 24 Feb 2015 13:19:30 +0800 Message-ID: Subject: Re: some question about aarch32 for ARM64 From: loody To: Catalin Marinas Cc: LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1463 Lines: 36 hi catalin: 2015-02-23 21:27 GMT+08:00 Catalin Marinas : > On Mon, Feb 23, 2015 at 12:28:57PM +0000, loody wrote: >> I follow below instructions to compile a simple c file as aarch32 but in vain. >> >> https://gcc.gnu.org/onlinedocs/gcc-4.9.1/gcc/AArch64-Options.html#AArch64-Options > > On the above link, there are no instructions on how to compile an > AArch32 application with the AArch64 compiler. You need an AArch32 gcc > (e.g. arm-linux-gnu-gcc, not aarch64-linux-gnu-gcc). > >> I saw there are aarch32 support in arm64 kernel porting. > > Yes, that's to support AArch32 binaries (ARMv8/v7/...). > >> Would you mind to let us know how to get aarch32 ELF for running on >> ARM64 processors? > > Just use the right compiler. > >> PS:Below is my compile error message: >> #aarch64-linux-gnu-gcc -mabi=ilp32 test.c > > -mabi=ilp32 is entirely different from an AArch32 compiler. The above > still generates AArch64 but with the ILP32 ABI (sizeof int/long/pointer > is 32-bit). so per your explanation, AArch32 binary could be created by any arm-linux-gnu-gcc which support armv7 and previous instructions. And -mabi=ilp32 is still aarch64 but with ILP32 ABI. appreciate your kind help ^^ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/