[PATCH] powerpc: Initialize local variable fdt to NULL in elf64_load()

[Segher Boessenkool]

On Thu, Apr 22, 2021 at 08:05:27AM +0000, David Laight wrote:
> > (Does anyone - and by anyone I mean any large distro - compile with
> > local variables inited by the compiler?)
> 
> There are compilers that initialise locals to zero for 'debug' builds
> and leave the 'random' for optimised 'release' builds.
> Lets not test what we are releasing!

Yeah, that's the worst of all possible worlds.

> I also think there is a new option to gcc (or clang?) to initialise
> on-stack structures and arrays to ensure garbage isn't passed.
> That seems to be a horrid performance hit!
> Especially in userspace where large stack allocations are almost free.
> 
> Any auto-initialise ought to be with a semi-random value
> (especially not zero) so that it is never right and doesn't
> lead to lazy coding.

Many compilers did something like this, decades ago -- for debug builds.


Segher