New comment by zlice on void-packages repository

https://github.com/void-linux/void-packages/pull/48480#issuecomment-1948405859

Comment:
i see `build-helper/rust.sh : 28` has `export BINDGEN_EXTRA_CLANG_ARGS+=" --sysroot=${XBPS_CROSS_BASE} -I${XBPS_CROSS_BASE}/usr/include"`

not sure how or where that's used? 1 or 2 other templates seem to have the var.

try this in mesa template? idk rust really but quick search points to the bindgen cross build var

```sh
  if [ "$CROSS_BUILD" ]; then
    BINDGEN_INCLUDE_FLAGS=$( $CPP -x c++ -v /dev/null -o /dev/null 2>&1 | \
      sed -n '/#include <...> search starts here:/,/End of search list./p' | \
      sed '1,1d;$d' | sed  's/^ /-I/' | paste -s )

    # fix compiler detection for botan:
    # https://github.com/randombit/botan/blob/63d51cb1ab08849d8ece329811b61f8c9abebbcf/configure.py#L2888
    export CXX="${XBPS_CROSS_TRIPLET}-g++"

    export BINDGEN_CFLAGS="--target=$XBPS_CROSS_TRIPLET \
      --sysroot=${XBPS_CROSS_BASE} ${BINDGEN_INCLUDE_FLAGS}"
```