Rollup merge of rust-lang#92214 - ehuss:submodule-bg-exit, r=Mark-Simulacrum

Error if submodule fetch fails.

In CI, if fetching a submodule fails, the script would exit successfully. Later parts of the build will fail due to the missing files, but it is a bit confusing, and I think it would be better to error out earlier.

The reason is that in bash, `wait` without arguments will exit 0 even if a background job exits with an error. The solution here is to wait on each individual job, which will return the exit code of the job.

This was encountered in rust-lang#92177.

Author: matthiaskrgr

src/ci/init_repo.sh

@@ -62,6 +62,7 @@ for i in ${!modules[@]}; do
         url=${urls[$i]}
         url=${url/\.git/}
         fetch_github_commit_archive $module "$url/archive/$commit.tar.gz" &
+        bg_pids[${i}]=$!
         continue
     else
         use_git="$use_git $module"
@@ -70,4 +71,9 @@ done
 retry sh -c "git submodule deinit -f $use_git && \
     git submodule sync && \
     git submodule update -j 16 --init --recursive $use_git"
-wait
+STATUS=0
+for pid in ${bg_pids[*]}
+do
+    wait $pid || STATUS=1
+done
+exit ${STATUS}