fix doc, disable bigint with old node

Author: dschuff

site/source/docs/tools_reference/settings_reference.rst

@@ -2186,10 +2186,9 @@ WASM_BIGINT
 
 WebAssembly integration with JavaScript BigInt. When enabled we don't need to
 legalize i64s into pairs of i32s, as the wasm VM will use a BigInt where an
-i64 is used. If WASM_BIGINT is present, the default minimum supported browser
-versions will be increased to the min version that supports BigInt.
+i64 is used.
 
-Default value: false
+Default value: true
 
 .. _emit_producers_section:
 

test/common.py

@@ -37,7 +37,7 @@
 from tools.shared import get_canonical_temp_dir, path_from_root
 from tools.utils import MACOS, WINDOWS, read_file, read_binary, write_binary, exit_with_error
 from tools.settings import COMPILE_TIME_SETTINGS
-from tools import shared, line_endings, building, config, utils
+from tools import shared, feature_matrix, line_endings, building, config, utils
 
 logger = logging.getLogger('common')
 
@@ -1085,6 +1085,8 @@ def setUp(self):
       if node_version < emcc_min_node_version:
         self.emcc_args += building.get_emcc_node_flags(node_version)
         self.emcc_args.append('-Wno-transpile')
+      if node_version < feature_matrix.min_browser_versions[feature_matrix.Feature.JS_BIGINT_INTEGRATION]
+        self.emcc_args.append('-sWASM_BIGINT=0')
 
     self.v8_args = ['--wasm-staging']
     self.env = {}