From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Thu, 17 Mar 2016 10:46:45 +0000 Subject: [PATCH] ARM: use --fix-v4bx to allow building ARMv4 with future gcc In-Reply-To: <12678426.5oeMNXL25J@wuerfel> References: <12678426.5oeMNXL25J@wuerfel> Message-ID: <20160317104645.GZ19428@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Mar 17, 2016 at 11:38:30AM +0100, Arnd Bergmann wrote: > Compiling with -march=armv4t leads the compiler to using 'bx reg' > instructions instead of 'ld pc,reg'. This is not supported on ITYM mov pc, reg > However, in order to still allow users of old toolchains to link > the kernel, we only pass the option to linkers that support it, > based on a $(ld-option ...) call. I'm intentionally passing the > flag to all linker versions here regardless of whether it's needed > or not, so we can more easily spot any regressions if something > goes wrong. > > For consistency, I'm passing the --fix-v4bx flag for both the > vmlinux final link and the individual loadable modules. > The module loader code already interprets the R_ARM_V4BX relocations > in loadable modules and converts bx instructions into ldr even MOV. -- RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.