https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124697
--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to H.J. Lu from comment #5)
> > Yes. This is wrong code. My patch would have fixed it, doing
> > effectively (but restricted to x86 at this point)
> >
> > diff --git a/gcc/function.cc b/gcc/function.cc
> > index 46c0d8b54c2..d44815afc16 100644
> > --- a/gcc/function.cc
> > +++ b/gcc/function.cc
> > @@ -2840,7 +2840,7 @@ assign_parm_adjust_stack_rtl (tree parm, struct
> > assign_parm_data_one *data)
> > MEM_ALIGN (stack_parm))))
> > || (data->nominal_type
> > && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
> > - && (MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY
> > + && (MEM_ALIGN (stack_parm) < BIGGEST_ALIGNMENT
>
> What happens if BIGGEST_ALIGNMENT > PREFERRED_STACK_BOUNDARY and
> BIGGEST_ALIGNMENT > MAX_SUPPORTED_STACK_ALIGNMENT.
Like this?
diff --git a/gcc/function.cc b/gcc/function.cc
index 46c0d8b54c2..109821c16fc 100644
--- a/gcc/function.cc
+++ b/gcc/function.cc
@@ -2840,7 +2840,8 @@ assign_parm_adjust_stack_rtl (tree parm, struct
assign_parm_data_one *data)
MEM_ALIGN (stack_parm))))
|| (data->nominal_type
&& TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
- && (MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY
+ && ((MEM_ALIGN (stack_parm)
+ < MIN (BIGGEST_ALIGNMENT, MAX_SUPPORTED_STACK_ALIGNMENT))
/* If its address is taken, make a local copy whose
maximum alignment is MAX_SUPPORTED_STACK_ALIGNMENT.
*/
>
> > /* If its address is taken, make a local copy whose
> > maximum alignment is MAX_SUPPORTED_STACK_ALIGNMENT.
> > */
> >
