Re: [PATCH] Predefine __STRICT_ALIGN__ if STRICT_ALIGNMENT

[Sam James <sam@gentoo.org>]

YunQiang Su <syq@gcc.gnu.org> writes:

> Arm32 predefines __ARM_FEATURE_UNALIGNED if -mno-unaligned-access,
> and RISC-V predefines __riscv_misaligned_avoid, while other ports
> that support -mstrict-align/-mno-unaligned-access don't have such
> macro, and these backend macros are only avaiable for c-family.
> Note: Arm64 always predefine __ARM_FEATURE_UNALIGNED: See #111555.

I would say tag the bug even if you're not fixing it, as it was related
enough for you to cite it.

>
> Let's add a generic one.
>
> __STRICT_ALIGN__ is used instead of __STRICT_ALIGNMENT__, due to that
> the later is used by some softwares, such as lzo2, syslinux etc.
>
> gcc
> 	* cppbuiltin.cc: Predefine __STRICT_ALIGNMENT__ if
> 	STRICT_ALIGNMENT.
> ---
>  gcc/cppbuiltin.cc | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/gcc/cppbuiltin.cc b/gcc/cppbuiltin.cc
> index c4bfc2917dc..d32efdf9a07 100644
> --- a/gcc/cppbuiltin.cc
> +++ b/gcc/cppbuiltin.cc
> @@ -123,6 +123,9 @@ define_builtin_macros_for_compilation_flags (cpp_reader *pfile)
>  
>    cpp_define_formatted (pfile, "__FINITE_MATH_ONLY__=%d",
>  			flag_finite_math_only);
> +
> +  if (STRICT_ALIGNMENT)
> +    cpp_define (pfile, "__STRICT_ALIGNMENT__");
>  }