> -----Original Message----- > From: David Marchand <david.march...@redhat.com> > Sent: Friday, November 27, 2020 4:39 PM > To: Ruifeng Wang <ruifeng.w...@arm.com>; jer...@marvell.com > Cc: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>; dev > <dev@dpdk.org>; nd <n...@arm.com>; Feifei Wang <feifei.wa...@arm.com> > Subject: Re: [dpdk-dev] [PATCH 1/2] eal/arm: fix gcc build for optimization > level 0 > > On Fri, Nov 27, 2020 at 9:10 AM Ruifeng Wang <ruifeng.w...@arm.com> > wrote: > > > > Gcc build with '-O0' on platforms with RTE_ARM_FEATURE_ATOMICS set > > failed for: > > ../lib/librte_efd/rte_efd.c > > Assembler messages: > > 3866: Error: selected processor does not support `crc32cb w0,w0,w1' > > 3890: Error: selected processor does not support `crc32ch w0,w0,w1' > > 3914: Error: selected processor does not support `crc32cw w0,w0,w1' > > 3938: Error: selected processor does not support `crc32cx w0,w0,x1' > > > > This was caused by an architecture specifier added for Clang. > > Unlike Clang, Gcc considers each inline assembly block to be dependent > > and therefor, the architecture specifier impacts assemble of some > > blocks require certain extension support. > > I reproduced this error with -O0 for config/arm/arm64_octeontx2_linux_gcc. > The patch looks simple enough and it only affects ARM builds. > > Jerin, > Are you okay with this change for 20.11? > Or should we wait 21.02? > > Ruifeng, > Looking at the kernel, I see no distinction with gcc/clang, so I'd say the > kernel > has the same issue, or is there something else that differs in dpdk? > Besides, the kernel patch previously mentioned had a followup fix.
The kernel follow up fix looks like a better way to reconcile Gcc and Clang. I'll reroll with the same approach. > > > -- > David Marchand
