Re: [OE-core] [PATCH] gcc: enable zstd compression of LTO bytecode

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Thu, 2022-02-03 at 18:26 +0100, Enrico Scholz via lists.openembedded.org
wrote:
> gcc-10+ supports zstd compression of LTO bytecode.  Install the
> corresponding package to enable this feature in a deterministic way.
> 
> NOTE: previously built LTO object files (without this compression)
> must be regenerated; gcc will fail else with
> 
>   | lto1: internal compiler error: original not compressed with zstd
> 
> in this case.
> 
> NOTE: it seems to be possible that zstd support is enabled non
> deterministically (perhaps by host system pollution).
> 
> I had the problem that the SDK gcc was built with zstd while the
> cross gcc was built without it.  Libraries (built by cross gcc and
> uncompressed hence) could not be used with the SDK gcc.
> 
> Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
> ---
>  meta/recipes-devtools/gcc/gcc-11.2.inc | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/meta/recipes-devtools/gcc/gcc-11.2.inc b/meta/recipes-devtools/gcc/gcc-11.2.inc
> index f07a5be507b3..62db035760aa 100644
> --- a/meta/recipes-devtools/gcc/gcc-11.2.inc
> +++ b/meta/recipes-devtools/gcc/gcc-11.2.inc
> @@ -11,7 +11,7 @@ BINV = "11.2.0"
>  FILESEXTRAPATHS =. "${FILE_DIRNAME}/gcc:${FILE_DIRNAME}/gcc/backport:"
>  
>  DEPENDS =+ "mpfr gmp libmpc zlib flex-native"
> -NATIVEDEPS = "mpfr-native gmp-native libmpc-native zlib-native flex-native"
> +NATIVEDEPS = "mpfr-native gmp-native libmpc-native zlib-native flex-native zstd-native"
>  
>  LICENSE = "GPL-3.0-with-GCC-exception & GPLv3"
>  

Should we be passing some flag to gcc explicitly to configure this
deterministicly?

Cheers,

Richard