lit: Fix a subtle resource usage bug when executing tests using the internal

shell runner.

We would inadvertently end up holding on to handles to the temporary files
longer than we should have been. On Win32, where open handles lock some file
operations, this caused problems in tests which would try to move temporary
files around (as Clang does by default now).

Many thanks to Francois Pichet for the excellent detective work on this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115040 91177308-0d34-0410-b5e6-96231b3b80d8

utils/lit/lit/TestRunner.py

@@ -178,6 +178,13 @@ def executeShCmd(cmd, cfg, cwd, results):
         else:
             input = subprocess.PIPE
 
+    # Explicitly close any redirected files. We need to do this now because we
+    # need to release any handles we may have on the temporary files (important
+    # on Win32, for example). Since we have already spawned the subprocess, our
+    # handles have already been transferred so we do not need them anymore.
+    for f in opened_files:
+        f.close()
+
     # FIXME: There is probably still deadlock potential here. Yawn.
     procData = [None] * len(procs)
     procData[-1] = procs[-1].communicate()
@@ -215,10 +222,6 @@ def executeShCmd(cmd, cfg, cwd, results):
         else:
             exitCode = res
 
-    # Explicitly close any redirected files.
-    for f in opened_files:
-        f.close()
-
     # Remove any named temporary files we created.
     for f in named_temp_files:
         try: