Issue 5216 - [emscripten] Use a more reliable way of retrieving mangled function name

compile

Index: compile
===================================================================
--- a/compile
+++ b/compile
@@ -36,17 +36,17 @@ GENERATION_PARAMS = {
     'NO_EXIT_RUNTIME': 1,
     'NO_DYNAMIC_EXECUTION': 1,
     'NO_FILESYSTEM': 1,
     'INVOKE_RUN': 0,
     'TEXTDECODER': 0,
     'EXPORTED_RUNTIME_METHODS': ['cwrap', 'ccall', 'stringToAscii'],
 }
 DEFINES = []
-ADDITIONAL_PARAMS = ['-O3', '-m32', '-std=gnu++14', '--memory-init-file', '0',
+ADDITIONAL_PARAMS = ['-O3', '-m32', '-std=c++1z', '--memory-init-file', '0',
                      '--emit-symbol-map', '-Wall', '-Werror', '-fno-exceptions',
                      '-fno-rtti', '--js-library', JS_LIBRARY]
 
 
 def get_source_files(phase):
     for (path, dirs, files) in os.walk(SOURCE_DIR):
         for f in files:
             if os.path.splitext(f)[1] != '.cpp':
@@ -70,17 +70,18 @@ def getenv(emscripten_config):
         'NODE_JS': scope.get('NODE_JS', 'node'),
     })
     return env
 
 
 def generate_bindings(env):
     params = [
         env['PYTHON'], os.path.join(env['EMSCRIPTEN'], 'emcc'),
-        '-o', BINDINGS_GENERATOR, '-std=gnu++14', '--js-library', JS_LIBRARY,
+        '-o', BINDINGS_GENERATOR, '-std=c++1z', '--js-library', JS_LIBRARY,
+        '--js-library', os.path.join(SOURCE_DIR, 'bindings', 'library.js'),
     ] + list(get_source_files('bindings'))
     subprocess.check_call(params, env=env)
 
     with open(BINDINGS_OUTPUT, 'w') as file:
         subprocess.check_call([env['NODE_JS'], BINDINGS_GENERATOR],
                               stdout=file)