Error when building c++ : libstdc++-v3: No support for this host/target combination.

[William Tambe]

We are porting GCC releases/gcc-10.1.0.

The following error is seen when building c++ .

configure: error: No support for this host/target combination.
make[1]: *** [Makefile:12511: configure-target-libstdc++-v3] Error 1
make[1]: Leaving directory '/gcc-build'
make: *** [Makefile:962: all] Error 2

We edited libgcc/config.host to add support for our port; we are
thinking there is a similar config file that needs to be edited to add
support for our port in libstdc++ .

Any idea which file need to be edited to support our port when
libstdc++ is being built ?