Re: Build failures with gcc 4.5 and older

[Guenter Roeck]

On 08/14/2018 04:20 PM, Linus Torvalds wrote:
> On Tue, Aug 14, 2018 at 4:02 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> > The m68k build still fails because 0cc3cd21657 ("cpu/hotplug: Boot HT
> > siblings at least once") was evidently never tested on CONFIG_SMP=n.
> > How could that come about - the patch is six weeks old??
>
> Ehh, meet the joys of embargoes.
>
> The code was tested (and people even found subtle arm64 problems due
> to that testing), but because it couldn't be made public until today,
> it didn't go through all the usual infrastructure we depend on.
>
> But:
>
> > kernel/cpu.c: In function 'boot_cpu_hotplug_init':
> > kernel/cpu.c:2275:2: error: 'struct cpuhp_cpu_state' has no member named 'booted_once'
>
> it should be fixed now in -git.
>
> > @@ -490,6 +490,8 @@ struct mm_struct {
> >   #endif
> >          } __randomize_layout;
> >
> > +       int wibble;
> > +
>
> Can we call this something informative? Like
>
>          int __gcc_4_4_is_garbage_that_shouldnt_be_used;
>
> or something?
>
> That is, if we actually want to really drag out this whole pointless
> pain of allowing ancient compilers?
>
> Guys, at some point we need to switch to 4.6. The people who feel the
> pain today *will* feel the pain at some point. Just get it over with
> already.

For my part I am all for making gcc 4.6 mandatory.

Guenter