Gcc/G++ compilation into NIOS 2 Assembly - c++

Question

I am trying to have gcc/g++ convert C or C++ code into assembly using the -S and -march commands but I am unable to find an exact answer as to whether it supports NIOS 2. --target shows a list of architectures but no obvious NIOS 2. THe GNU compiler website DOES contain a list of NIOS 2 commands. https://gcc.gnu.org/onlinedocs/gcc/Nios-II-Options.html
Does anyone know the -march architecture required for the compiler or whether support was dropped in a previous version? Currently using gcc 7.3
-v Dump 13:58
Using built-in specs.
COLLECT_GCC=gcc
OFFLOAD_TARGET_NAMES=nvptx-none
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 7.3.0-27ubuntu1~18.04' --with-bugurl=file:///usr/share/doc/gcc-7/README.Bugs --enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++ --prefix=/usr --with-gcc-major-version-only --program-suffix=-7 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --enable-default-pie --with-system-zlib --with-target-system-zlib --enable-objc-gc=auto --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-offload-targets=nvptx-none --without-cuda-driver --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 7.3.0 (Ubuntu 7.3.0-27ubuntu1~18.04)
COLLECT_GCC_OPTIONS='-o' 'test' '-S' '-O3' '-march=nios2' '-v'
/usr/lib/gcc/x86_64-linux-gnu/7/cc1plus -quiet -v -imultiarch x86_64-linux-gnu -D_GNU_SOURCE loop.cpp -quiet -dumpbase loop.cpp -march=nios2 -auxbase-strip test -O3 -version -o test -fstack-protector-strong -Wformat -Wformat-security
GNU C++14 (Ubuntu 7.3.0-27ubuntu1~18.04) version 7.3.0 (x86_64-linux-gnu)
compiled by GNU C version 7.3.0, GMP version 6.1.2, MPFR version 4.0.1, MPC version 1.1.0, isl version isl-0.19-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/7"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/7/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/include/c++/7
/usr/include/x86_64-linux-gnu/c++/7
/usr/include/c++/7/backward
/usr/lib/gcc/x86_64-linux-gnu/7/include
/usr/local/include
/usr/lib/gcc/x86_64-linux-gnu/7/include-fixed
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
cc1plus: error: bad value (‘nios2’) for ‘-march=’ switch
cc1plus: note: valid arguments to ‘-march=’ switch are: nocona core2 nehalem corei7 westmere sandybridge corei7-avx ivybridge core-avx-i haswell core-avx2 broadwell skylake skylake-avx512 bonnell atom silvermont slm knl x86-64 eden-x2 nano nano-1000 nano-2000 nano-3000 nano-x2 eden-x4 nano-x4 k8 k8-sse3 opteron opteron-sse3 athlon64 athlon64-sse3 athlon-fx amdfam10 barcelona bdver1 bdver2 bdver3 bdver4 znver1 btver1 btver2
GNU C++14 (Ubuntu 7.3.0-27ubuntu1~18.04) version 7.3.0 (x86_64-linux-gnu)
compiled by GNU C version 7.3.0, GMP version 6.1.2, MPFR version 4.0.1, MPC version 1.1.0, isl version isl-0.19-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072

Answer 1

Your compiler only includes support for the x86 targets (x86-64, i386 and its variantsm and the x32 x86-64 subset). The multilib and multiarch bits refer to something else, not multiple targets.
I don't think there are pre-built cross-compilers targeting NIOS or NIOS 2 as part of Ubuntu (not even universe), so you probably have to build a cross-toolchain yourself, starting with a cross-binutils.