1 files changed, 1 insertions, 0 deletions
diff --git a/emscripten.py b/emscripten.py
index 7f8b5505..5c9275c2 100755
--- a/emscripten.py
+++ b/emscripten.py
@@ -748,6 +748,7 @@ def emscript_fast(infile, settings, outfile, libraries=[], compiler_engine=None,
     backend_args += ['-emscripten-reserved-function-pointers=%d' % settings['RESERVED_FUNCTION_POINTERS']]
   if settings['ASSERTIONS'] > 0:
     backend_args += ['-emscripten-assertions=%d' % settings['ASSERTIONS']]
+  backend_args += ['-O' + str(settings['OPT_LEVEL'])]
   if DEBUG:
     logging.debug('emscript: llvm backend: ' + ' '.join(backend_args))
     t = time.time()