diff --git a/ChangeLog.md b/ChangeLog.md
index fd7f53ca469a9..5728cfd5b67db 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -20,6 +20,9 @@ See docs/process.md for more on how version tagging works.
 
 5.0.3 (in development)
 ----------------------
+- The low level FS.write API now only accepts TypedArray.  The higher level
+  writeFile and createDataFile file still also accept string and Array.
+  (#26413)
 - Warn on usage of the deprecated `EMSCRIPTEN` macro (`__EMSCRIPTEN__` should
   be used instead). (#26381)
 - The `-sRELOCATABLE` setting was effectively removed (moved to legacy
diff --git a/src/lib/libcore.js b/src/lib/libcore.js
index 29c4794c6a39e..fa3c9654d77e8 100644
--- a/src/lib/libcore.js
+++ b/src/lib/libcore.js
@@ -2193,7 +2193,7 @@ addToLibrary({
 #endif
       FS.createPath('/', PATH.dirname(name), true, true);
       // canOwn this data in the filesystem, it is a slice of wasm memory that will never change
-      FS.createDataFile(name, null, HEAP8.subarray(content, content + len), true, true, true);
+      FS.createDataFile(name, null, HEAP8.subarray(content, content + len), true, true, /*canOwn=*/true);
     } while ({{{ makeGetValue('ptr', '0', '*') }}});
 #if RUNTIME_DEBUG
     dbg('done preloading data files');
diff --git a/src/lib/libfs.js b/src/lib/libfs.js
index 196866d2c31ab..d148c84f5a2d2 100644
--- a/src/lib/libfs.js
+++ b/src/lib/libfs.js
@@ -7,6 +7,7 @@
 var LibraryFS = {
   $FS__deps: ['$randomFill', '$PATH', '$PATH_FS', '$TTY', '$MEMFS',
     '$FS_modeStringToFlags',
+    '$FS_fileDataToTypedArray',
     '$FS_getMode',
     '$intArrayFromString',
 #if LibraryManager.has('libidbfs.js')
@@ -1253,9 +1254,13 @@ FS.staticInit();`;
 #endif
       return bytesRead;
     },
+    /**
+     * @param {TypedArray} buffer
+     */
     write(stream, buffer, offset, length, position, canOwn) {
 #if ASSERTIONS
       assert(offset >= 0);
+      assert(buffer.subarray, 'FS.write expects a TypedArray');
 #endif
       if (length < 0 || position < 0) {
         throw new FS.ErrnoError({{{ cDefs.EINVAL }}});
@@ -1346,17 +1351,14 @@ FS.staticInit();`;
       FS.close(stream);
       return buf;
     },
+    /**
+     * @param {TypedArray|Array|string} data
+     */
     writeFile(path, data, opts = {}) {
       opts.flags = opts.flags || {{{ cDefs.O_TRUNC | cDefs.O_CREAT | cDefs.O_WRONLY }}};
       var stream = FS.open(path, opts.flags, opts.mode);
-      if (typeof data == 'string') {
-        data = new Uint8Array(intArrayFromString(data, true));
-      }
-      if (ArrayBuffer.isView(data)) {
-        FS.write(stream, data, 0, data.byteLength, undefined, opts.canOwn);
-      } else {
-        abort('Unsupported data type');
-      }
+      data = FS_fileDataToTypedArray(data);
+      FS.write(stream, data, 0, data.byteLength, undefined, opts.canOwn);
       FS.close(stream);
     },
 
@@ -1604,6 +1606,9 @@ FS.staticInit();`;
       var mode = FS_getMode(canRead, canWrite);
       return FS.create(path, mode);
     },
+    /**
+     * @param {TypedArray|Array|string=} data
+     */
     createDataFile(parent, name, data, canRead, canWrite, canOwn) {
       var path = name;
       if (parent) {
@@ -1613,11 +1618,7 @@ FS.staticInit();`;
       var mode = FS_getMode(canRead, canWrite);
       var node = FS.create(path, mode);
       if (data) {
-        if (typeof data == 'string') {
-          var arr = new Array(data.length);
-          for (var i = 0, len = data.length; i < len; ++i) arr[i] = data.charCodeAt(i);
-          data = arr;
-        }
+        data = FS_fileDataToTypedArray(data);
         // make sure we can write to the file
         FS.chmod(node, mode | {{{ cDefs.S_IWUGO }}});
         var stream = FS.open(node, {{{ cDefs.O_TRUNC | cDefs.O_CREAT | cDefs.O_WRONLY }}});
diff --git a/src/lib/libfs_shared.js b/src/lib/libfs_shared.js
index a80f7332157ad..838b52309701a 100644
--- a/src/lib/libfs_shared.js
+++ b/src/lib/libfs_shared.js
@@ -107,6 +107,16 @@ addToLibrary({
     return mode;
   },
 
+  $FS_fileDataToTypedArray: (data) => {
+    if (typeof data == 'string') {
+      data = intArrayFromString(data, true);
+    }
+    if (!data.subarray) {
+      data = new Uint8Array(data);
+    }
+    return data;
+  },
+
   $FS_stdin_getChar_buffer: [],
 
   // getChar has 3 particular return values:
diff --git a/src/lib/libmemfs.js b/src/lib/libmemfs.js
index cb9c60c6028aa..cfa5b56be7e00 100644
--- a/src/lib/libmemfs.js
+++ b/src/lib/libmemfs.js
@@ -248,16 +248,23 @@ addToLibrary({
         return size;
       },
 
-      // Writes the byte range (buffer[offset], buffer[offset+length]) to offset 'position' into the file pointed by 'stream'
-      // canOwn: A boolean that tells if this function can take ownership of the passed in buffer from the subbuffer portion
-      //         that the typed array view 'buffer' points to. The underlying ArrayBuffer can be larger than that, but
-      //         canOwn=true will not take ownership of the portion outside the bytes addressed by the view. This means that
-      //         with canOwn=true, creating a copy of the bytes is avoided, but the caller shouldn't touch the passed in range
-      //         of bytes anymore since their contents now represent file data inside the filesystem.
+      /**
+       * Writes the byte range (buffer[offset], buffer[offset+length]) to offset
+       * 'position' into the file pointed by 'stream'.
+       * @param {TypedArray} buffer
+       * @param {boolean=} canOwn - A boolean that tells if this function can
+       *     take ownership of the passed in buffer from the subbuffer portion
+       *     that the typed array view 'buffer' points to. The underlying
+       *     ArrayBuffer can be larger than that, but canOwn=true will not take
+       *     ownership of the portion outside the bytes addressed by the view.
+       *     This means that with canOwn=true, creating a copy of the bytes is
+       *     avoided, but the caller shouldn't touch the passed in range of
+       *     bytes anymore since their contents now represent file data inside
+       *     the filesystem.
+       */
       write(stream, buffer, offset, length, position, canOwn) {
 #if ASSERTIONS
-        // The data buffer should be a typed array view
-        assert(!(buffer instanceof ArrayBuffer));
+        assert(buffer.subarray, 'FS.write expects a TypedArray');
 #endif
 #if ALLOW_MEMORY_GROWTH
         // If the buffer is located in main memory (HEAP), and if
@@ -273,35 +280,21 @@ addToLibrary({
         var node = stream.node;
         node.mtime = node.ctime = Date.now();
 
-        if (buffer.subarray) { // This write is from a typed array to a typed array?
-          if (canOwn) {
+        if (canOwn) {
 #if ASSERTIONS
-            assert(position === 0, 'canOwn must imply no weird position inside the file');
+          assert(position === 0, 'canOwn must imply no weird position inside the file');
 #endif
-            node.contents = buffer.subarray(offset, offset + length);
-            node.usedBytes = length;
-            return length;
-          } else if (node.usedBytes === 0 && position === 0) { // If this is a simple first write to an empty file, do a fast set since we don't need to care about old data.
-            node.contents = buffer.slice(offset, offset + length);
-            node.usedBytes = length;
-            return length;
-          } else if (position + length <= node.usedBytes) { // Writing to an already allocated and used subrange of the file?
-            node.contents.set(buffer.subarray(offset, offset + length), position);
-            return length;
-          }
-        }
-
-        // Appending to an existing file and we need to reallocate, or source data did not come as a typed array.
-        MEMFS.expandFileStorage(node, position+length);
-        if (buffer.subarray) {
+          node.contents = buffer.subarray(offset, offset + length);
+          node.usedBytes = length;
+        } else if (node.usedBytes === 0 && position === 0) { // If this is a simple first write to an empty file, do a fast set since we don't need to care about old data.
+          node.contents = buffer.slice(offset, offset + length);
+          node.usedBytes = length;
+        } else {
+          MEMFS.expandFileStorage(node, position+length);
           // Use typed array write which is available.
           node.contents.set(buffer.subarray(offset, offset + length), position);
-        } else {
-          for (var i = 0; i < length; i++) {
-            node.contents[position + i] = buffer[offset + i]; // Or fall back to manual write if not.
-          }
+          node.usedBytes = Math.max(node.usedBytes, position + length);
         }
-        node.usedBytes = Math.max(node.usedBytes, position + length);
         return length;
       },
 
diff --git a/src/lib/libwasmfs.js b/src/lib/libwasmfs.js
index d168e9f6acde7..5a4f29ede10c3 100644
--- a/src/lib/libwasmfs.js
+++ b/src/lib/libwasmfs.js
@@ -509,20 +509,17 @@ addToLibrary({
     return FS_mknod(path, mode, 0);
   },
 
-  $FS_writeFile__deps: ['_wasmfs_write_file', '$stackSave', '$stackRestore', 'malloc', 'free'],
+  $FS_writeFile__deps: ['$FS_fileDataToTypedArray', '_wasmfs_write_file', '$stackSave', '$stackRestore', 'malloc', 'free'],
   $FS_writeFile: (path, data) => {
     var sp = stackSave();
     var pathBuffer = stringToUTF8OnStack(path);
-    var len = typeof data == 'string' ? lengthBytesUTF8(data) + 1 : data.length;
+    data = FS_fileDataToTypedArray(data);
+    var len = data.length;
     var dataBuffer = _malloc(len);
 #if ASSERTIONS
     assert(dataBuffer);
 #endif
-    if (typeof data == 'string') {
-      len = stringToUTF8(data, dataBuffer, len);
-    } else {
-      HEAPU8.set(data, dataBuffer);
-    }
+    HEAPU8.set(data, dataBuffer);
     var ret = __wasmfs_write_file(pathBuffer, dataBuffer, len);
     _free(dataBuffer);
     stackRestore(sp);
diff --git a/test/codesize/test_codesize_cxx_ctors1.json b/test/codesize/test_codesize_cxx_ctors1.json
index b81c460b78f7e..54988716516f0 100644
--- a/test/codesize/test_codesize_cxx_ctors1.json
+++ b/test/codesize/test_codesize_cxx_ctors1.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19334,
-  "a.out.js.gz": 8012,
+  "a.out.js": 19214,
+  "a.out.js.gz": 7982,
   "a.out.nodebug.wasm": 132865,
   "a.out.nodebug.wasm.gz": 49889,
-  "total": 152199,
-  "total_gz": 57901,
+  "total": 152079,
+  "total_gz": 57871,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_ctors2.json b/test/codesize/test_codesize_cxx_ctors2.json
index 45575af3fbc93..4de0debeda7dd 100644
--- a/test/codesize/test_codesize_cxx_ctors2.json
+++ b/test/codesize/test_codesize_cxx_ctors2.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19311,
-  "a.out.js.gz": 7998,
+  "a.out.js": 19191,
+  "a.out.js.gz": 7968,
   "a.out.nodebug.wasm": 132285,
   "a.out.nodebug.wasm.gz": 49542,
-  "total": 151596,
-  "total_gz": 57540,
+  "total": 151476,
+  "total_gz": 57510,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_except.json b/test/codesize/test_codesize_cxx_except.json
index 4a858c94f0f87..b3169d1dc9f6e 100644
--- a/test/codesize/test_codesize_cxx_except.json
+++ b/test/codesize/test_codesize_cxx_except.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 22995,
-  "a.out.js.gz": 8989,
+  "a.out.js": 22875,
+  "a.out.js.gz": 8959,
   "a.out.nodebug.wasm": 172743,
   "a.out.nodebug.wasm.gz": 57374,
-  "total": 195738,
-  "total_gz": 66363,
+  "total": 195618,
+  "total_gz": 66333,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index 4d817c28b7be8..ce9b1467a28b3 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19145,
-  "a.out.js.gz": 7934,
+  "a.out.js": 19025,
+  "a.out.js.gz": 7906,
   "a.out.nodebug.wasm": 148138,
   "a.out.nodebug.wasm.gz": 55261,
-  "total": 167283,
-  "total_gz": 63195,
+  "total": 167163,
+  "total_gz": 63167,
   "sent": [
     "_abort_js",
     "_tzset_js",
diff --git a/test/codesize/test_codesize_cxx_except_wasm_legacy.json b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
index eae00c3da2fa4..52a6429d34191 100644
--- a/test/codesize/test_codesize_cxx_except_wasm_legacy.json
+++ b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19219,
-  "a.out.js.gz": 7954,
+  "a.out.js": 19099,
+  "a.out.js.gz": 7926,
   "a.out.nodebug.wasm": 145944,
   "a.out.nodebug.wasm.gz": 54887,
-  "total": 165163,
-  "total_gz": 62841,
+  "total": 165043,
+  "total_gz": 62813,
   "sent": [
     "_abort_js",
     "_tzset_js",
diff --git a/test/codesize/test_codesize_cxx_lto.json b/test/codesize/test_codesize_cxx_lto.json
index 9ed7da2c85026..b171846c1991f 100644
--- a/test/codesize/test_codesize_cxx_lto.json
+++ b/test/codesize/test_codesize_cxx_lto.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 18682,
-  "a.out.js.gz": 7697,
+  "a.out.js": 18562,
+  "a.out.js.gz": 7670,
   "a.out.nodebug.wasm": 102126,
   "a.out.nodebug.wasm.gz": 39426,
-  "total": 120808,
-  "total_gz": 47123,
+  "total": 120688,
+  "total_gz": 47096,
   "sent": [
     "a (emscripten_resize_heap)",
     "b (_setitimer_js)",
diff --git a/test/codesize/test_codesize_cxx_mangle.json b/test/codesize/test_codesize_cxx_mangle.json
index 7861934ee3137..5a79291878812 100644
--- a/test/codesize/test_codesize_cxx_mangle.json
+++ b/test/codesize/test_codesize_cxx_mangle.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23045,
-  "a.out.js.gz": 9008,
+  "a.out.js": 22925,
+  "a.out.js.gz": 8978,
   "a.out.nodebug.wasm": 239177,
   "a.out.nodebug.wasm.gz": 79774,
-  "total": 262222,
-  "total_gz": 88782,
+  "total": 262102,
+  "total_gz": 88752,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_noexcept.json b/test/codesize/test_codesize_cxx_noexcept.json
index a55086a4d111d..26057d45ca943 100644
--- a/test/codesize/test_codesize_cxx_noexcept.json
+++ b/test/codesize/test_codesize_cxx_noexcept.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19334,
-  "a.out.js.gz": 8012,
+  "a.out.js": 19214,
+  "a.out.js.gz": 7982,
   "a.out.nodebug.wasm": 134872,
   "a.out.nodebug.wasm.gz": 50724,
-  "total": 154206,
-  "total_gz": 58736,
+  "total": 154086,
+  "total_gz": 58706,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_file_preload.expected.js b/test/codesize/test_codesize_file_preload.expected.js
index 91e332a2e6b7f..a38f00ebe5427 100644
--- a/test/codesize/test_codesize_file_preload.expected.js
+++ b/test/codesize/test_codesize_file_preload.expected.js
@@ -1196,34 +1196,19 @@ var MEMFS = {
       if (!length) return 0;
       var node = stream.node;
       node.mtime = node.ctime = Date.now();
-      if (buffer.subarray) {
-        // This write is from a typed array to a typed array?
-        if (canOwn) {
-          node.contents = buffer.subarray(offset, offset + length);
-          node.usedBytes = length;
-          return length;
-        } else if (node.usedBytes === 0 && position === 0) {
-          // If this is a simple first write to an empty file, do a fast set since we don't need to care about old data.
-          node.contents = buffer.slice(offset, offset + length);
-          node.usedBytes = length;
-          return length;
-        } else if (position + length <= node.usedBytes) {
-          // Writing to an already allocated and used subrange of the file?
-          node.contents.set(buffer.subarray(offset, offset + length), position);
-          return length;
-        }
-      }
-      // Appending to an existing file and we need to reallocate, or source data did not come as a typed array.
-      MEMFS.expandFileStorage(node, position + length);
-      if (buffer.subarray) {
+      if (canOwn) {
+        node.contents = buffer.subarray(offset, offset + length);
+        node.usedBytes = length;
+      } else if (node.usedBytes === 0 && position === 0) {
+        // If this is a simple first write to an empty file, do a fast set since we don't need to care about old data.
+        node.contents = buffer.slice(offset, offset + length);
+        node.usedBytes = length;
+      } else {
+        MEMFS.expandFileStorage(node, position + length);
         // Use typed array write which is available.
         node.contents.set(buffer.subarray(offset, offset + length), position);
-      } else {
-        for (var i = 0; i < length; i++) {
-          node.contents[position + i] = buffer[offset + i];
-        }
+        node.usedBytes = Math.max(node.usedBytes, position + length);
       }
-      node.usedBytes = Math.max(node.usedBytes, position + length);
       return length;
     },
     llseek(stream, offset, whence) {
@@ -1301,6 +1286,16 @@ var FS_modeStringToFlags = str => {
   return flags;
 };
 
+var FS_fileDataToTypedArray = data => {
+  if (typeof data == "string") {
+    data = intArrayFromString(data, true);
+  }
+  if (!data.subarray) {
+    data = new Uint8Array(data);
+  }
+  return data;
+};
+
 var FS_getMode = (canRead, canWrite) => {
   var mode = 0;
   if (canRead) mode |= 292 | 73;
@@ -2490,14 +2485,8 @@ var FS = {
   writeFile(path, data, opts = {}) {
     opts.flags = opts.flags || 577;
     var stream = FS.open(path, opts.flags, opts.mode);
-    if (typeof data == "string") {
-      data = new Uint8Array(intArrayFromString(data, true));
-    }
-    if (ArrayBuffer.isView(data)) {
-      FS.write(stream, data, 0, data.byteLength, undefined, opts.canOwn);
-    } else {
-      abort("Unsupported data type");
-    }
+    data = FS_fileDataToTypedArray(data);
+    FS.write(stream, data, 0, data.byteLength, undefined, opts.canOwn);
     FS.close(stream);
   },
   cwd: () => FS.currentPath,
@@ -2724,11 +2713,7 @@ var FS = {
     var mode = FS_getMode(canRead, canWrite);
     var node = FS.create(path, mode);
     if (data) {
-      if (typeof data == "string") {
-        var arr = new Array(data.length);
-        for (var i = 0, len = data.length; i < len; ++i) arr[i] = data.charCodeAt(i);
-        data = arr;
-      }
+      data = FS_fileDataToTypedArray(data);
       // make sure we can write to the file
       FS.chmod(node, mode | 146);
       var stream = FS.open(node, 577);
diff --git a/test/codesize/test_codesize_file_preload.json b/test/codesize/test_codesize_file_preload.json
index 9579e98d43373..df9ad46824a2a 100644
--- a/test/codesize/test_codesize_file_preload.json
+++ b/test/codesize/test_codesize_file_preload.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 22289,
-  "a.out.js.gz": 9239,
+  "a.out.js": 22140,
+  "a.out.js.gz": 9187,
   "a.out.nodebug.wasm": 1681,
   "a.out.nodebug.wasm.gz": 960,
-  "total": 23970,
-  "total_gz": 10199,
+  "total": 23821,
+  "total_gz": 10147,
   "sent": [
     "a (fd_write)"
   ],
diff --git a/test/codesize/test_codesize_files_js_fs.json b/test/codesize/test_codesize_files_js_fs.json
index 7a186e0ba07d9..ed6d9bccc4b10 100644
--- a/test/codesize/test_codesize_files_js_fs.json
+++ b/test/codesize/test_codesize_files_js_fs.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 17953,
-  "a.out.js.gz": 7339,
+  "a.out.js": 17833,
+  "a.out.js.gz": 7310,
   "a.out.nodebug.wasm": 381,
   "a.out.nodebug.wasm.gz": 260,
-  "total": 18334,
-  "total_gz": 7599,
+  "total": 18214,
+  "total_gz": 7570,
   "sent": [
     "a (fd_write)",
     "b (fd_read)",
diff --git a/test/codesize/test_codesize_hello_O0.json b/test/codesize/test_codesize_hello_O0.json
index bf3b397ca4ba0..3ecd463f27324 100644
--- a/test/codesize/test_codesize_hello_O0.json
+++ b/test/codesize/test_codesize_hello_O0.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 24239,
-  "a.out.js.gz": 8714,
+  "a.out.js": 24263,
+  "a.out.js.gz": 8725,
   "a.out.nodebug.wasm": 15138,
   "a.out.nodebug.wasm.gz": 7455,
-  "total": 39377,
-  "total_gz": 16169,
+  "total": 39401,
+  "total_gz": 16180,
   "sent": [
     "fd_write"
   ],
diff --git a/test/codesize/test_codesize_hello_dylink.json b/test/codesize/test_codesize_hello_dylink.json
index 7f24a526d7a58..2c172700f2583 100644
--- a/test/codesize/test_codesize_hello_dylink.json
+++ b/test/codesize/test_codesize_hello_dylink.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 26376,
-  "a.out.js.gz": 11261,
+  "a.out.js": 26256,
+  "a.out.js.gz": 11231,
   "a.out.nodebug.wasm": 17730,
   "a.out.nodebug.wasm.gz": 8957,
-  "total": 44106,
-  "total_gz": 20218,
+  "total": 43986,
+  "total_gz": 20188,
   "sent": [
     "__syscall_stat64",
     "emscripten_resize_heap",
diff --git a/test/codesize/test_codesize_hello_dylink_all.json b/test/codesize/test_codesize_hello_dylink_all.json
index 8dedb57b8f3dd..1a6cba8395cca 100644
--- a/test/codesize/test_codesize_hello_dylink_all.json
+++ b/test/codesize/test_codesize_hello_dylink_all.json
@@ -1,7 +1,7 @@
 {
-  "a.out.js": 244462,
+  "a.out.js": 244330,
   "a.out.nodebug.wasm": 577692,
-  "total": 822154,
+  "total": 822022,
   "sent": [
     "IMG_Init",
     "IMG_Load",
diff --git a/test/codesize/test_codesize_minimal_O0.expected.js b/test/codesize/test_codesize_minimal_O0.expected.js
index 08922367380bb..cdf31f4dc0ee5 100644
--- a/test/codesize/test_codesize_minimal_O0.expected.js
+++ b/test/codesize/test_codesize_minimal_O0.expected.js
@@ -1051,6 +1051,7 @@ Module['FS_createPreloadedFile'] = FS.createPreloadedFile;
   'FS_preloadFile',
   'FS_modeStringToFlags',
   'FS_getMode',
+  'FS_fileDataToTypedArray',
   'FS_stdin_getChar',
   'FS_mkdirTree',
   '_setNetworkCallback',
diff --git a/test/codesize/test_codesize_minimal_O0.json b/test/codesize/test_codesize_minimal_O0.json
index 8baef8820d3cb..ca88e74a19508 100644
--- a/test/codesize/test_codesize_minimal_O0.json
+++ b/test/codesize/test_codesize_minimal_O0.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19425,
-  "a.out.js.gz": 6992,
+  "a.out.js": 19449,
+  "a.out.js.gz": 7006,
   "a.out.nodebug.wasm": 1136,
   "a.out.nodebug.wasm.gz": 656,
-  "total": 20561,
-  "total_gz": 7648,
+  "total": 20585,
+  "total_gz": 7662,
   "sent": [],
   "imports": [],
   "exports": [
diff --git a/test/codesize/test_unoptimized_code_size.json b/test/codesize/test_unoptimized_code_size.json
index 197c9407eb0b3..635a347810bec 100644
--- a/test/codesize/test_unoptimized_code_size.json
+++ b/test/codesize/test_unoptimized_code_size.json
@@ -1,16 +1,16 @@
 {
-  "hello_world.js": 56978,
-  "hello_world.js.gz": 17726,
+  "hello_world.js": 57007,
+  "hello_world.js.gz": 17736,
   "hello_world.wasm": 15138,
   "hello_world.wasm.gz": 7455,
   "no_asserts.js": 26576,
   "no_asserts.js.gz": 8881,
   "no_asserts.wasm": 12187,
   "no_asserts.wasm.gz": 5984,
-  "strict.js": 54796,
-  "strict.js.gz": 17024,
+  "strict.js": 54825,
+  "strict.js.gz": 17039,
   "strict.wasm": 15138,
   "strict.wasm.gz": 7450,
-  "total": 180813,
-  "total_gz": 64520
+  "total": 180871,
+  "total_gz": 64545
 }