Attempt to build all cross-compile targets supported by `rustc` and report the time taken.

x-compile-test

#!/bin/sh -eu

FILTER="${FILTER:="."}"
TOOLCHAIN_BK="$(rustup toolchain list | rg default | awk '{print $1}')"
TOOLCHAIN_KIND_BK="$(echo "$TOOLCHAIN_BK" | rg -o '^(stable|nightly)')"
if [ "$TOOLCHAIN_KIND_BK" != "stable" ]; then
  rustup install stable
  rustup default stable
fi

TARGETS="$(rustc --print target-list | rg "$FILTER")"

echo "=== Installing targets."
for target in $TARGETS; do
  echo "+ $target"
  rustup target add "$target" 1>/dev/null 2>&1 || true
done
echo "=== Compiling with collected targets."
for target in $TARGETS; do
  cargo clean 1>/dev/null 2>&1
  export RUSTC_WRAPPER=
  export RUSTFLAGS=
  cargo build --target="$target" 2>&1 | awk "/Finished/{ rc = 1; print \"+ $target in\", \$8 }; END { exit !rc }" || echo "- $target"
done

if [ "$TOOLCHAIN_KIND_BK" != "stable" ]; then
  rustup default "$TOOLCHAIN_BK"
fi