diff --git a/config/Makefile.in b/config/Makefile.in
index b0668816aa8..0e340f9c8e2 100644
--- a/config/Makefile.in
+++ b/config/Makefile.in
@@ -113,7 +113,7 @@ STL_WRAPPERS_SENTINEL = $(DIST)/stl_wrappers/sentinel
 
 $(STL_WRAPPERS_SENTINEL): $(srcdir)/make-stl-wrappers.py $(srcdir)/$(stl_compiler)-stl-wrapper.template.h $(srcdir)/stl-headers $(GLOBAL_DEPS)
 	$(PYTHON) $(srcdir)/make-stl-wrappers.py stl_wrappers $(stl_compiler) $(srcdir)/$(stl_compiler)-stl-wrapper.template.h $(srcdir)/stl-headers
-	$(PYTHON) $(srcdir)/nsinstall.py stl_wrappers $(DIST)
+	$(PYTHON) $(srcdir)/nsinstall.py -t stl_wrappers $(DIST)
 	touch $(STL_WRAPPERS_SENTINEL)
 
 export:: $(STL_WRAPPERS_SENTINEL)
diff --git a/config/make-stl-wrappers.py b/config/make-stl-wrappers.py
index ebecdf4109d..6e5f3f7e3cd 100644
--- a/config/make-stl-wrappers.py
+++ b/config/make-stl-wrappers.py
@@ -3,6 +3,7 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 from __future__ import print_function
 import os, re, string, sys
+from mozbuild.util import FileAvoidWrite
 
 def find_in_path(file, searchpath):
     for dir in searchpath.split(os.pathsep):
@@ -37,13 +38,10 @@ def main(outdir, compiler, template_file, header_list_file):
             continue
 
         path = header_path(header, compiler)
-        try:
-            f = open(os.path.join(outdir, header), 'w')
+        with FileAvoidWrite(os.path.join(outdir, header)) as f:
             f.write(string.Template(template).substitute(HEADER=header,
                                                          HEADER_PATH=path,
                                                          NEW_HEADER_PATH=path_to_new))
-        finally:
-            f.close()
 
 
 if __name__ == '__main__':