I downloaded and unzipped arm-gnu-toolchain-11.3.rel1-mingw-w64-i686-aarch64-none-linux-gnu.zip on Win10.
In the release notes, "Invoking GCC", file <install-dir>\bin\gccvar.bat is mentioned but the file does not exist in the distributed zip file.
I also couldn't find the gccvar.bat file in arm-gnu-toolchain-11.3.rel1-mingw-w64-i686-arm-none-eabi.exe