[U-Boot] [PATCH 1/2] Makefile: Use -fno-strict-aliasing globally

[Tom Rini]

On Thu, Sep 20, 2018 at 11:37:36AM +0800, Bin Meng wrote:
> Hi Tom,
> 
> On Mon, Sep 17, 2018 at 1:30 PM Bin Meng <bmeng.cn at gmail.com> wrote:
> >
> > The -fstrict-aliasing option is implicitly enabled at levels -O2,
> > -O3, -Os by GCC. This option allows the compiler to assume the
> > strictest aliasing rules applicable to the language being compiled.
> > For example, the practice of reading from a different union member
> > than the one most recently written to (called "type-punning") is
> > common. In this case, "type-punning" only works if the memory is
> > accessed through the union type, but might not work by taking the
> > address, casting the resulting pointer and dereferencing the result,
> > which is an undefined behavior per the "strict aliasing rules".
> >
> > GCC's -Wstrict-aliasing (included in -Wall) option does not catch
> > all cases, but does attempt to catch the more common pitfalls. So
> > there are cases that GCC does not report but the codes are violating
> > the "strict aliasing rules".
> >
> > Given lots of codes that may be written to rely on "type-punning",
> > and Linux kernel disables it by -fno-strict-aliasing globally, since
> > U-Boot currently does this on nds32/riscv/x86 builds only, extend
> > this for all architecture builds.
> >
> > Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
> > Reviewed-by: Tom Rini <trini at konsulko.com>
> > Reviewed-by: Simon Glass <sjg at chromium.org>
> > ---
> >
> >  Makefile | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> 
> When will this series be applied? Another risc-v series has conflicts
> in [PATCH 2/2] and if this is applied in mainline, I can respin my
> risc-v series on top of this to save some time for Rick's handle it
> himself.

I will try and get to this soon, thanks for your patience.

-- 
Tom
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