[PATCH 2/2] speakup: only build serialio when ISA is enabled

Samuel Thibault samuel.thibault at ens-lyon.org
Tue Aug 4 12:11:35 EDT 2020

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.


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