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Date:   Tue, 4 Aug 2020 18:11:35 +0200
From:   Samuel Thibault <samuel.thibault@ens-lyon.org>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-serial@vger.kernel.org, speakup@linux-speakup.org
Subject: Re: [PATCH 2/2] speakup: only build serialio when ISA is enabled
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Greg KH, le mar. 04 août 2020 17:49:52 +0200, a ecrit:
> > #define inb(c)		({ u8  __v; __io_pbr(); __v = readb_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
> > 
> > and thus yes it's arithmetic over a (void*) pointer, the caller cannot
> > do anything about it.
> 
> And that's fine, math with pointers, even void ones, is ok.

C++ doesn't like it, but in general compilers provide some semantic for
it, yes.

> I wonder why riscv was complaining about that.  It's not nice, but it is
> valid C.

Strictly C speaking, no, but GNU C yes.

> Let's see if any of their developers care about it :)

Ok :) In the meanwhile I sent a v2 series that should fix the different
link cases, just not the particular riscv warning.

Samuel