Isolated emscripten in new lib

lib/emscripten/emtests/test_bigarray.c

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2016 The Emscripten Authors.  All rights reserved.
+ * Emscripten is available under two separate licenses, the MIT license and the
+ * University of Illinois/NCSA Open Source License.  Both these licenses can be
+ * found in the LICENSE file.
+ */
+
+// avoid "array initializer too large" errors
+#include <stdio.h>
+#include <assert.h>
+
+#define SIZE (1024 * 100)
+struct Struct {
+  char x;
+  int y;
+};
+Struct buffy[SIZE];
+
+int main() {
+  for (int i = 0; i < SIZE; i++) {
+    assert(buffy[i].x == 0 && buffy[i].y == 0);
+  }  // we were zeroinitialized
+  for (int i = 0; i < SIZE; i++) {
+    buffy[i].x = i * i;
+    buffy[i].y = i * i * i;
+  }  // we can save data
+  printf("*%d*\n", buffy[SIZE / 3].x);
+  return 0;
+}