fixup! ci: Reduce redundant commands in build.sh

ci/build.sh

@@ -20,17 +20,24 @@ if [ "$TOOLCHAIN" = "nightly" ] ; then
 fi
 
 test_target() {
-    build_cmd="${1}"
-    target="${2}"
-    no_std="${3}"
+    target="${1}"
+    no_dist="${2:0}"
 
     RUSTFLAGS="${RUSTFLAGS:-}"
 
     # The basic command that is run each time
-    cmd="cargo +$rust $build_cmd --target $target"
+    cmd="cargo +$rust build --target $target"
 
-    # If there is a std component, fetch it:
-    if [ "${no_std}" != "1" ]; then
+    if [ "${no_dist}" == "0" ]; then
+        # If we can't download a `core`, we need to build it
+        cmd="$cmd -Zbuild-std=core,alloc"
+
+        # FIXME: With `build-std` feature, `compiler_builtins` emits a lof of lint warnings.
+        RUSTFLAGS="${RUSTFLAGS:-} -Aimproper_ctypes_definitions"
+        export RUSTFLAGS
+    else
+        # Otherwise it is available for download; fetch it:
+
         # FIXME: rustup often fails to download some artifacts due to network
         # issues, so we retry this N times.
         N=5
@@ -42,12 +49,6 @@ test_target() {
             n=$((n+1))
             sleep 1
         done
-
-        # FIXME: With `build-std` feature, `compiler_builtins` emits a lof of lint warnings.
-        RUSTFLAGS="${RUSTFLAGS:-} -Aimproper_ctypes_definitions"
-        export RUSTFLAGS
-
-        cmd="$cmd -Zbuild-std=core,alloc"
     fi
 
     # Test with expected combinations of features
@@ -152,9 +153,9 @@ for target in $targets; do
     if echo "$target" | grep -q "$filter"; then
         if [ "${OS}" = "windows" ]; then
             TARGET="$target" ./ci/install-rust.sh
-            test_target build "$target"
+            test_target "$target"
         else
-            test_target build "$target"
+            test_target "$target"
         fi
 
         test_run=1
@@ -231,7 +232,7 @@ x86_64-wrs-vxworks \
 if [ "${rust}" = "nightly" ] && [ "${OS}" = "linux" ]; then
     for target in $rust_linux_no_core_targets; do
         if echo "$target" | grep -q "$filter"; then
-            test_target build "$target" 1
+            test_target "$target" 1
         fi
 
         test_run=1
@@ -247,7 +248,7 @@ i386-apple-ios \
 if [ "${rust}" = "nightly" ] && [ "${OS}" = "macos" ]; then
     for target in $rust_apple_no_core_targets; do
         if echo "$target" | grep -q "$filter"; then
-            test_target build "$target" 1
+            test_target "$target" 1
         fi
 
         test_run=1