[FFmpeg-devel] [PATCH] configure: Do not abort when cross-compiling to the native CPU

[David Michael]

On Sat, Mar 7, 2020 at 10:32 AM David Michael <fedora.dm0 at gmail.com> wrote:
> Using a compiler with a different host triplet is considered
> cross-compiling, even when it is for the same architecture as the
> build system.  With such a cross-compiler, it is still valid to
> optimize builds with --cpu=host.  Drop the condition that aborts in
> this case, since a cross-compiler for an incompatible architecture
> will fail with -mtune=native anyway.
>
> Signed-off-by: David Michael <fedora.dm0 at gmail.com>
> ---
>
> Hi,
>
> I am building software in a ChromeOS-style environment where the native
> build system creates a cross-compiler with a different vendor string for
> each supported architecture, and cross-compiled packages are installed
> into their own root directory.  The build system's architecture is not
> handled any differently, so packages compatible with the native
> architecture are still technically being cross-compiled.
>
> When I changed settings to tune for the native CPU so I can produce an
> installation optimized to run on the build system hardware, FFmpeg fails
> from this seemingly redundant test.  Can it just be dropped?
>
> Thanks.
>
> David
>
>  configure | 3 ---
>  1 file changed, 3 deletions(-)
>
> diff --git a/configure b/configure
> index 06e3a7b2a8..69ffdeb3ed 100755
> --- a/configure
> +++ b/configure
> @@ -4785,9 +4785,6 @@ if test -n "$sysroot"; then
>  fi
>
>  if test "$cpu" = host; then
> -    enabled cross_compile &&
> -        die "--cpu=host makes no sense when cross-compiling."
> -
>      case "$cc_type" in
>          gcc|llvm_gcc)
>              check_native(){
> --
> 2.21.1

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