Hi Masahiro,
Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote on Tue, 22 Jan
2019 17:00:54 +0900:
> On Tue, Jan 22, 2019 at 4:50 PM Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
> >
> > Hi Masahiro,
> >
> > Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> wrote on Tue, 22 Jan
> > 2019 16:42:55 +0900:
> >
> > > Although drivers do not directly get access to the private data of
> > > instruction patterns, let's use unnamed union field to be consistent
> > > with nand_op_instr.
> > >
> >
> > Actually this is how we wrote it the first time. Then we got robots
> > reporting that anonymous unions where not allowed with older (still
> > supported) GCC versions and I had to do this:
> >
> >
> > commit c1a72e2dbb4abb90bd408480d7c48ba40cb799ce
> > Author: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
> > Date: Fri Jan 19 19:11:27 2018 +0100
> >
> > mtd: nand: Fix build issues due to an anonymous union
> >
> > GCC-4.4.4 raises errors when assigning a parameter in an anonymous
> > union, leading to this kind of failure:
> >
> > drivers/mtd/nand/marvell_nand.c:1936:
> > warning: missing braces around initializer
> > warning: (near initialization for '(anonymous)[1].<anonymous>')
> > error: unknown field 'data' specified in initializer
> > error: unknown field 'addr' specified in initializer
> >
> > Work around the situation by naming these unions.
> >
> > Fixes: 8878b126df76 ("mtd: nand: add ->exec_op() implementation")
> > Reported-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx>
> > Tested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
> >
>
>
> Hmm, how come Andrew's compiler was fine with the following?
>
> struct nand_flash_dev {
> char *name;
> union {
> struct {
> uint8_t mfr_id;
> uint8_t dev_id;
> };
> uint8_t id[NAND_MAX_ID_LEN];
> };
> unsigned int pagesize;
> ...
> };
>
It is probably not :)
>
>
> The current minimum version is GCC 4.6
> (commit cafa0010cd51fb7)
> but I am not sure if this restriction is remaining.
>
That's right, can you please test if this limitation is still
ongoing wit GCC 4.6?
Thanks,
Miquèl
