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Date:   Mon, 12 Aug 2019 08:03:48 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Charles Papon <charles.papon.90@gmail.com>
Cc:     Bin Meng <bmeng.cn@gmail.com>, Atish Patra <atish.patra@wdc.com>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Paul Walmsley <paul.walmsley@sifive.com>
Subject: Re: [PATCH] riscv: kbuild: drop CONFIG_RISCV_ISA_C
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On Thu, Aug 08, 2019 at 02:18:53PM +0200, Charles Papon wrote:
> Please do not drop it.
> 
> Compressed instruction extension has some specific overhead in small
> RISC-V FPGA softcore, especialy in the ones which can't implement the
> register file read in a asynchronous manner because of the FPGA
> technology.
> What are reasons to enforce RVC ?

Because it it the unix platform baseline as stated in the patch.