These binaries were cross-compiled on Windows 8 using Toolchain at http://sysprogs.com/getfile/566/raspberry-gcc8.3.0.exe for Raspbian Buster but should work on both Raspberry Pi 3 and 4.
Please note that even if Raspberry Pi 3 and 4 has a 64-bit CPU Raspbian uses a 32-bit kernel and this is why we provide armv7l binaries instead of arm64-a.
More toolchains at https://gnutoolchains.com/raspberry/