Run the .NET Core SDK docker image and share your working directory containing your .csproj file at /home in the container.
On Linux/macOS:
docker run --interactive --tty --rm --volume "$(pwd):/home" mcr.microsoft.com/dotnet/core/sdk:2.2 /bin/bash
On Windows:
set pwd=/%cd:\=/%
docker run --interactive --tty --rm --volume "%pwd::=%:/home" mcr.microsoft.com/dotnet/core/sdk:2.2 /bin/bash
cd /home
dotnet tool install --global dotnet-warp
/root/.dotnet/tools/dotnet-warp -l aggressive
The binary is produced in the working directory.
Note that CoreRT is an experimental .NET Core runtime optimized for AOT so it's not really surprising that it doesn't work.
Installing clang-3.9 is required else we get this error:
/root/.nuget/packages/microsoft.dotnet.ilcompiler/1.0.0-alpha-27910-01/build/Microsoft.NETCore.Native.Unix.props(109,5): error : Platform linker ('clang-3.9') not found. Try installing clang-3.9 or the appropriate package for your platform to resolve the problem.
apt update
apt --yes install clang-3.9
rm -r bin obj
dotnet add package --source https://dotnetfeed.blob.core.windows.net/dotnet-core/index.json Microsoft.DotNet.ILCompiler -v 1.0.0-alpha-*
dotnet publish --source https://dotnetfeed.blob.core.windows.net/dotnet-core/index.json --runtime linux-x64 --configuration Release
On a real console app with a few dependencies (CommandLineParser, CsvHelper, FluentEmail, EntityFrameworkCore + Npgsql, Serilog) the compilation failed after 67 minutes with the following error:
Process is terminating due to StackOverflowException. /root/.nuget/packages/microsoft.dotnet.ilcompiler/1.0.0-alpha-28007-01/build/Microsoft.NETCore.Native.targets(249,5): error MSB3073: The command ""/root/.nuget/packages/runtime.linux-x64.microsoft.dotnet.ilcompiler/1.0.0-alpha-28007-01/tools/ilc" @"obj/Release/netcoreapp2.2/linux-x64/native/my-console-app.ilc.rsp"" exited with code 134.
See CoreRT issues #6372 Process is terminating due to StackOverflowException and #363 Detect infinite generic expansion on GitHub.
docker run --interactive --tty --rm --volume "$(pwd):/home" mcr.microsoft.com/dotnet/core/sdk:3.0 /bin/bash
In the container:
cd /home
dotnet publish --runtime linux-x64 --configuration Release /p:TargetFramework=netcoreapp3.0 /p:PublishSingleFile=true /p:PublishTrimmed=true
The binary is produced in bin/Release/netcoreapp3.0/linux-x64/publish.
See also Announcing .NET Core 3.0 Preview 6, The PublishTrimmed Flag With IL Linker and https://aka.ms/dotnet-illink
Might be worth investigating Trim and Link as described in Reducing the size of self-contained .NET Core applications