[package] ffmpeg/5.0: report Unknown OS 'gnueabi' while cross compile

[CryptonymAMS]

Description

I was attempting to cross-compile some code on ubuntu using a cmd as
conan create . xxxx -pr:b default -pr:h rv1126 --build missing

the default profile is

[settings]
os=Linux
os_build=Linux
arch=x86_64
arch_build=x86_64
compiler=gcc
compiler.version=9
compiler.libcxx=libstdc++11
build_type=Release
[options]
[build_requires]
[env]

while the rv1126 profile is

[settings]
os=Linux
arch=armv7
compiler=gcc
compiler.version=8.3
compiler.libcxx=libstdc++11
build_type=Release

[build_requires]
rv1126/8.3.0@screenshare_public/stable

The combination of rv1126 profile will lead tools.get_gnu_triplet("Linux","armv7","gcc") to return gnueabi，but --target-os= option doesn't support it，then report Unknown OS 'gnueabi and stop compile.

The related code at conanfile.py（ffmpeg/5.0） is

       if tools.cross_building(self):
            if self._target_os == "emscripten":
                args.append("--target-os=none")
            else:
                args.append("--target-os={}".format(self._target_os))

   def _target_os(self):
        if self._is_msvc:
            return "win32"
        else:
            _, _, target_os = tools.get_gnu_triplet(
                "Macos" if tools.is_apple_os(
                    self.settings.os) else str(self.settings.os),
                str(self.settings.arch),
                str(self.settings.compiler) if self.settings.os == "Windows" else None,
            ).split("-")
            if target_os == "gnueabihf":
                target_os = "gnu" # could also be "linux"
            return target_os

Package and Environment Details

• Package Name/Version: ffmpeg/5.0
• Operating System+version: Linux Ubuntu 20.04
• Compiler+version: GCC 8
• Docker image: conanio/gcc8
• Conan version: conan 1.58.0
• Python version: Python 3.8.10

Conan profile

[settings]
os=Linux
arch=armv7
compiler=gcc
compiler.version=8.3
compiler.libcxx=libstdc++11
build_type=Release

[build_requires]
rv1126/8.3.0@screenshare_public/stable

Steps to reproduce

use cmd to cross-compile code which requiring ffmpeg/5.0
conan create . xxxx -pr:b default -pr:h rv1126 --build missing

The host profile is:

[settings]
os=Linux
arch=armv7
compiler=gcc
compiler.version=8.3
compiler.libcxx=libstdc++11
build_type=Release

Just like a simple demo following,it will return gnueabi which option "--target-os=" doesn't support:

target_os = tools.get_gnu_triplet("Linux","armv7","gcc")
print(target_os)

Logs

Click to expand log

ffmpeg/5.0: Applying build-requirement: rv1126/8.3.0@screenshare_public/stable
ffmpeg/5.0: Applying build-requirement: pkgconf/1.7.4
ffmpeg/5.0: WARN: Build folder is dirty, removing it: /home/hao/.conan/data/ffmpeg/5.0///build/e075b4f4491320467d8995247d10f1fe84c9d7ee
ffmpeg/5.0: Copying sources to build folder
ffmpeg/5.0: Building your package in /home/hao/.conan/data/ffmpeg/5.0///build/e075b4f4491320467d8995247d10f1fe84c9d7ee
ffmpeg/5.0: Aggregating env generators
ffmpeg/5.0: Calling build()
ffmpeg/5.0: Calling:

source_subfolder/configure '--pkg-config-flags=--static' '--disable-doc' '--enable-cross-compile' '--enable-asm' '--disable-shared' '--enable-static' '--enable-pic' '--disable-avdevice' '--enable-avcodec' '--disable-avformat' '--enable-swresample' '--disable-swscale' '--disable-postproc' '--disable-avfilter' '--disable-bzlib' '--disable-zlib' '--disable-lzma' '--disable-iconv' '--disable-libopenjpeg' '--disable-libopenh264' '--disable-libvorbis' '--disable-libopus' '--disable-libzmq' '--disable-sdl2' '--disable-libx264' '--disable-libx265' '--disable-libvpx' '--disable-libmp3lame' '--disable-libfdk-aac' '--disable-libwebp' '--disable-openssl' '--disable-alsa' '--disable-libpulse' '--disable-vaapi' '--disable-vdpau' '--disable-libxcb' '--disable-libxcb-shm' '--disable-libxcb-shape' '--disable-libxcb-xfixes' '--disable-appkit' '--disable-avfoundation' '--disable-coreimage' '--disable-audiotoolbox' '--disable-videotoolbox' '--disable-securetransport' '--disable-cuda' '--disable-cuvid' '--disable-nonfree' '--disable-gpl' '--disable-everything' '--disable-encoders' '--disable-decoders' '--disable-hwaccels' '--disable-muxers' '--disable-demuxers' '--disable-parsers' '--disable-bsfs' '--disable-protocols' '--disable-devices' '--disable-indevs' '--disable-outdevs' '--disable-filters' '--enable-decoder=aac' '--enable-decoder=alac' '--disable-muxer=True' '--disable-vulkan' '--arch=arm' '--disable-programs' '--as=arm-linux-gnueabihf-as' '--cc=arm-linux-gnueabihf-gcc' '--cxx=arm-linux-gnueabihf-g++' '--target-os=gnueabi' '--extra-cflags=' '--extra-ldflags=' '--prefix=/home/hao/.conan/data/ffmpeg/5.0///package/e075b4f4491320467d8995247d10f1fe84c9d7ee' '--bindir=${prefix}/bin' '--libdir=${prefix}/lib'
Unknown OS 'gnueabi'.

[CryptonymAMS]

sorry my fault ,I pull old version code because of the local server cache.The lastest work.