PublishAot should have better error messages when cross-compiling #88942
Description
I tried to follow the excellent guidance at https://devblogs.microsoft.com/dotnet/improving-multiplatform-container-support/. I knew it wouldn't work, but wanted to see the error case. We seem to be relying on the underlying toolchain for the error case here. It's a bit rough given the guidance for the other scenarios. I'd like to see a better error message.
7.098 Generating native code
9.915 ILC: Method '[releasejsonapp]Program.<Main>$(string[])' will always throw because: Failed to load assembly 'Microsoft.AspNetCore'
13.60 /usr/bin/ld.bfd: unrecognised emulation mode: elf_x86_64
13.61 Supported emulations: aarch64linux aarch64elf aarch64elf32 aarch64elf32b aarch64elfb armelf armelfb aarch64linuxb aarch64linux32 aarch64linux32b armelfb_linux_eabi armelf_linux_eabi
13.63 clang-16 : error : linker command failed with exit code 1 (use -v to see invocation) [/source/releasejsonapp.csproj]
13.64 /root/.nuget/packages/microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/build/Microsoft.NETCore.Native.targets(364,5): error MSB3073: The command ""clang" "obj/Release/net8.0/linux-musl-x64/native/releasejsonapp.o" -o "bin/Release/net8.0/linux-musl-x64/native/releasejsonapp" -fuse-ld=bfd /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/sdk/libbootstrapper.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/sdk/libRuntime.ServerGC.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/sdk/libeventpipe-enabled.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/sdk/libstdc++compat.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/framework/libSystem.Native.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/framework/libSystem.IO.Compression.Native.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/framework/libSystem.Net.Security.Native.a /root/.nuget/packages/runtime.linux-musl-x64.microsoft.dotnet.ilcompiler/8.0.0-preview.6.23329.7/framework/libSystem.Security.Cryptography.Native.OpenSsl.a --target=x86_64-alpine-linux-musl -g '-Wl,-rpath,$ORIGIN' -Wl,--build-id=sha1 -Wl,--as-needed -pthread -ldl -lz -lrt -lm -pie -Wl,-pie -Wl,-z,relro -Wl,-z,now -Wl,--eh-frame-hdr -Wl,--discard-all -Wl,--gc-sections" exited with code 1. [/source/releasejsonapp.csproj]