From 86c18212b16bad46e85fa0c44090a6731c0ef8af Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sun, 26 Jan 2020 17:55:07 +0200
Subject: [PATCH 01/17] More tests working with MINIMAL_RUNTIME in Wasm
 backend. ASan support to MINIMAL_RUNTIME.

---
 emcc.py                | 3 +++
 src/library_syscall.js | 4 ++++
 tests/test_core.py     | 5 +++++
 3 files changed, 12 insertions(+)

diff --git a/emcc.py b/emcc.py
index 4ba8a6b9c3583..4d75558ecb9f8 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1723,6 +1723,9 @@ def is_supported_link_flag(f):
         if shared.Settings.LINKABLE:
           exit_with_error('LSan does not support dynamic linking')
 
+        if shared.Settings.MINIMAL_RUNTIME:
+          exit_with_error('MINIMAL_RUNTIME is currently not compatible LSan')
+
       if 'address' in sanitize:
         shared.Settings.USE_ASAN = 1
 
diff --git a/src/library_syscall.js b/src/library_syscall.js
index ba8442ae44dc0..d3b1a419688e4 100644
--- a/src/library_syscall.js
+++ b/src/library_syscall.js
@@ -227,9 +227,13 @@ var SyscallsLibrary = {
   _emscripten_syscall_mmap2__deps: ['memalign', 'memset', '$SYSCALLS',
 #if FILESYSTEM && SYSCALLS_REQUIRE_FILESYSTEM
     '$FS',
+#endif
+#if MINIMAL_RUNTIME // MINIMAL_RUNTIME does not have a global PAGE_SIZE runtime variable.
+    'getpagesize'
 #endif
   ],
   _emscripten_syscall_mmap2: function(addr, len, prot, flags, fd, off) {
+#endif
     off <<= 12; // undo pgoffset
     var ptr;
     var allocated = false;
diff --git a/tests/test_core.py b/tests/test_core.py
index 2e8b667d449f2..131389ab9455f 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -5164,6 +5164,7 @@ def test_utf8_invalid(self):
       self.do_run(open(path_from_root('tests', 'utf8_invalid.cpp')).read(), 'OK.')
 
   # Test that invalid character in UTF8 does not cause decoding to crash.
+  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   @no_emterpreter
   def test_minimal_runtime_utf8_invalid(self):
     self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['UTF8ToString', 'stringToUTF8'])
@@ -8432,6 +8433,7 @@ def test_no_declare_asm_module_exports(self):
 
   # Tests that building with -s DECLARE_ASM_MODULE_EXPORTS=0 works
   @no_emterpreter
+  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_no_declare_asm_module_exports(self):
     self.set_setting('DECLARE_ASM_MODULE_EXPORTS', 0)
     self.set_setting('WASM_ASYNC_COMPILATION', 0)
@@ -8468,6 +8470,7 @@ def test_minimal_runtime_hello_printf(self, args):
 
   # Tests that -s MINIMAL_RUNTIME=1 works well with SAFE_HEAP
   @no_emterpreter
+  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_safe_heap(self):
     self.emcc_args = ['-s', 'MINIMAL_RUNTIME=1', '-s', 'SAFE_HEAP=1']
     self.maybe_closure()
@@ -8475,6 +8478,7 @@ def test_minimal_runtime_safe_heap(self):
 
   # Tests global initializer with -s MINIMAL_RUNTIME=1
   @no_emterpreter
+  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_global_initializer(self):
     self.set_setting('MINIMAL_RUNTIME', 1)
     self.maybe_closure()
@@ -8777,6 +8781,7 @@ def test_emscripten_get_exported_function(self):
     self.do_run_in_out_file_test('tests', 'core', 'test_get_exported_function')
 
   # Tests the emscripten_get_exported_function() API.
+  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_emscripten_get_exported_function(self):
     # Could also test with -s ALLOW_TABLE_GROWTH=1
     self.set_setting('RESERVED_FUNCTION_POINTERS', 2)

From c6750f31a2a6cba9fe755e95574633ecd8931711 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sun, 26 Jan 2020 17:57:06 +0200
Subject: [PATCH 02/17] LSan works too

---
 emcc.py            | 3 ---
 tests/test_core.py | 5 -----
 2 files changed, 8 deletions(-)

diff --git a/emcc.py b/emcc.py
index 4d75558ecb9f8..4ba8a6b9c3583 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1723,9 +1723,6 @@ def is_supported_link_flag(f):
         if shared.Settings.LINKABLE:
           exit_with_error('LSan does not support dynamic linking')
 
-        if shared.Settings.MINIMAL_RUNTIME:
-          exit_with_error('MINIMAL_RUNTIME is currently not compatible LSan')
-
       if 'address' in sanitize:
         shared.Settings.USE_ASAN = 1
 
diff --git a/tests/test_core.py b/tests/test_core.py
index 131389ab9455f..2e8b667d449f2 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -5164,7 +5164,6 @@ def test_utf8_invalid(self):
       self.do_run(open(path_from_root('tests', 'utf8_invalid.cpp')).read(), 'OK.')
 
   # Test that invalid character in UTF8 does not cause decoding to crash.
-  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   @no_emterpreter
   def test_minimal_runtime_utf8_invalid(self):
     self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['UTF8ToString', 'stringToUTF8'])
@@ -8433,7 +8432,6 @@ def test_no_declare_asm_module_exports(self):
 
   # Tests that building with -s DECLARE_ASM_MODULE_EXPORTS=0 works
   @no_emterpreter
-  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_no_declare_asm_module_exports(self):
     self.set_setting('DECLARE_ASM_MODULE_EXPORTS', 0)
     self.set_setting('WASM_ASYNC_COMPILATION', 0)
@@ -8470,7 +8468,6 @@ def test_minimal_runtime_hello_printf(self, args):
 
   # Tests that -s MINIMAL_RUNTIME=1 works well with SAFE_HEAP
   @no_emterpreter
-  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_safe_heap(self):
     self.emcc_args = ['-s', 'MINIMAL_RUNTIME=1', '-s', 'SAFE_HEAP=1']
     self.maybe_closure()
@@ -8478,7 +8475,6 @@ def test_minimal_runtime_safe_heap(self):
 
   # Tests global initializer with -s MINIMAL_RUNTIME=1
   @no_emterpreter
-  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_global_initializer(self):
     self.set_setting('MINIMAL_RUNTIME', 1)
     self.maybe_closure()
@@ -8781,7 +8777,6 @@ def test_emscripten_get_exported_function(self):
     self.do_run_in_out_file_test('tests', 'core', 'test_get_exported_function')
 
   # Tests the emscripten_get_exported_function() API.
-  @no_lsan('TODO: LSan with MINIMAL_RUNTIME')
   def test_minimal_runtime_emscripten_get_exported_function(self):
     # Could also test with -s ALLOW_TABLE_GROWTH=1
     self.set_setting('RESERVED_FUNCTION_POINTERS', 2)

From 2d41a68492dce0f135f021cf6677344839464321 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 28 Jan 2020 11:49:15 +0200
Subject: [PATCH 03/17] Enable more of the core test suite to build on
 MINIMAL_RUNTIME.

---
 src/deps_info.json          | 14 ++++++-------
 src/library.js              | 40 +++++++++++++++++++++++++++++--------
 src/library_nodefs.js       |  4 ++++
 src/library_pthread_stub.js | 16 ++++-----------
 src/library_strings.js      |  5 ++++-
 src/library_syscall.js      |  3 +++
 src/library_wasi.js         | 10 +++++++---
 src/modules.js              | 32 ++++++++++++++++-------------
 src/settings.js             |  2 +-
 9 files changed, 80 insertions(+), 46 deletions(-)

diff --git a/src/deps_info.json b/src/deps_info.json
index 8914d7a5dbd4f..7103bbe808c50 100644
--- a/src/deps_info.json
+++ b/src/deps_info.json
@@ -80,13 +80,13 @@
   "sleep": ["usleep"],
   "recv": ["htons"],
   "send": ["htons"],
-  "ctime": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "ctime_r": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "localtime": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "localtime_r": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "mktime": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "timegm": ["_get_tzname", "_get_daylight", "_get_timezone"],
-  "tzset": ["_get_tzname", "_get_daylight", "_get_timezone"],
+  "ctime": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "ctime_r": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "localtime": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "localtime_r": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "mktime": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "timegm": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
+  "tzset": ["_get_tzname", "_get_daylight", "_get_timezone", "malloc"],
   "emscripten_set_canvas_element_size_calling_thread": ["emscripten_async_queue_on_thread_"],
   "emscripten_webgl_destroy_context": ["emscripten_webgl_make_context_current", "emscripten_webgl_get_current_context"],
   "emscripten_webgl_create_context": ["malloc", "free"],
diff --git a/src/library.js b/src/library.js
index 005ce6f41cfb8..6af32cc831f9e 100644
--- a/src/library.js
+++ b/src/library.js
@@ -746,7 +746,7 @@ LibraryManager.library = {
   // to limitations in the system libraries (we can't easily add a global
   // ctor to create the environment without it always being linked in with
   // libc).
-  __buildEnvironment__deps: ['$ENV'],
+  __buildEnvironment__deps: ['$ENV', '_get_executable_name'],
   __buildEnvironment: function(environ) {
     // WARNING: Arbitrary limit!
     var MAX_ENV_VALUES = 64;
@@ -765,7 +765,7 @@ LibraryManager.library = {
       ENV['HOME'] = '/home/web_user';
       // Browser language detection #8751
       ENV['LANG'] = ((typeof navigator === 'object' && navigator.languages && navigator.languages[0]) || 'C').replace('-', '_') + '.UTF-8';
-      ENV['_'] = thisProgram;
+      ENV['_'] = __get_executable_name();
       // Allocate memory.
 #if !MINIMAL_RUNTIME // TODO: environment support in MINIMAL_RUNTIME
       poolPtr = getMemory(TOTAL_ENV_SIZE);
@@ -1844,12 +1844,12 @@ LibraryManager.library = {
     }
   },
 
-  dladdr__deps: ['$stringToNewUTF8'],
+  dladdr__deps: ['$stringToNewUTF8', '_get_executable_name'],
   dladdr__proxy: 'sync',
   dladdr__sig: 'iii',
   dladdr: function(addr, info) {
     // report all function pointers as coming from this program itself XXX not really correct in any way
-    var fname = stringToNewUTF8(thisProgram || './this.program'); // XXX leak
+    var fname = __get_executable_name(); // XXX leak
     {{{ makeSetValue('info', 0, 'fname', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE, '0', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE*2, '0', 'i32') }}};
@@ -2068,6 +2068,9 @@ LibraryManager.library = {
   // Note: glibc has one fewer underscore for all of these. Also used in other related functions (timegm)
   tzset__proxy: 'sync',
   tzset__sig: 'v',
+#if MINIMAL_RUNTIME
+  tzset__deps: ['$allocateUTF8'],
+#endif
   tzset: function() {
     // TODO: Use (malleable) environment variables instead of system settings.
     if (_tzset.called) return;
@@ -2091,8 +2094,8 @@ LibraryManager.library = {
     };
     var winterName = extractZone(winter);
     var summerName = extractZone(summer);
-    var winterNamePtr = allocate(intArrayFromString(winterName), 'i8', ALLOC_NORMAL);
-    var summerNamePtr = allocate(intArrayFromString(summerName), 'i8', ALLOC_NORMAL);
+    var winterNamePtr = allocateUTF8(winterName);
+    var summerNamePtr = allocateUTF8(summerName);
     if (summer.getTimezoneOffset() < winter.getTimezoneOffset()) {
       // Northern hemisphere
       {{{ makeSetValue('__get_tzname()', '0', 'winterNamePtr', 'i32') }}};
@@ -2158,7 +2161,11 @@ LibraryManager.library = {
 
   // Note: this is not used in STANDALONE_WASM mode, because it is more
   //       compact to do it in JS.
-  strftime__deps: ['_isLeapYear', '_arraySum', '_addDays', '_MONTH_DAYS_REGULAR', '_MONTH_DAYS_LEAP'],
+  strftime__deps: ['_isLeapYear', '_arraySum', '_addDays', '_MONTH_DAYS_REGULAR', '_MONTH_DAYS_LEAP'
+#if MINIMAL_RUNTIME
+    , '$intArrayFromString'
+#endif
+  ],
   strftime: function(s, maxsize, format, tm) {
     // size_t strftime(char *restrict s, size_t maxsize, const char *restrict format, const struct tm *restrict timeptr);
     // http://pubs.opengroup.org/onlinepubs/009695399/functions/strftime.html
@@ -2481,7 +2488,11 @@ LibraryManager.library = {
     return _strftime(s, maxsize, format, tm); // no locale support yet
   },
 
-  strptime__deps: ['_isLeapYear', '_arraySum', '_addDays', '_MONTH_DAYS_REGULAR', '_MONTH_DAYS_LEAP'],
+  strptime__deps: ['_isLeapYear', '_arraySum', '_addDays', '_MONTH_DAYS_REGULAR', '_MONTH_DAYS_LEAP'
+#if MINIMAL_RUNTIME
+    , '$intArrayFromString'
+#endif
+  ],
   strptime: function(buf, format, tm) {
     // char *strptime(const char *restrict buf, const char *restrict format, struct tm *restrict tm);
     // http://pubs.opengroup.org/onlinepubs/009695399/functions/strptime.html
@@ -5149,6 +5160,19 @@ LibraryManager.library = {
   __handle_stack_overflow: function() {
     abort('stack overflow')
   },
+
+  _get_executable_name: function() {
+#if MINIMAL_RUNTIME // MINIMAL_RUNTIME does not have a global runtime variable thisProgram
+#if ENVIRONMENT_MAY_BE_NODE
+    if (ENVIRONMENT_IS_NODE && process['argv'].length > 1) {
+      return process['argv'][1].replace(/\\/g, '/');
+    }
+#endif
+    return "./this.program";
+#else
+    return thisProgram || './this.program';
+#endif
+  },
 };
 
 function autoAddDeps(object, name) {
diff --git a/src/library_nodefs.js b/src/library_nodefs.js
index 780c15ecf3053..415da896a49f1 100644
--- a/src/library_nodefs.js
+++ b/src/library_nodefs.js
@@ -34,11 +34,15 @@ mergeInto(LibraryManager.library, {
     },
     convertNodeCode: function(e) {
       var code = e.code;
+#if ASSERTIONS
       assert(code in ERRNO_CODES);
+#endif
       return ERRNO_CODES[code];
     },
     mount: function (mount) {
+#if ASSERTIONS
       assert(ENVIRONMENT_IS_NODE);
+#endif
       return NODEFS.createNode(null, '/', NODEFS.getMode(mount.opts.root), 0);
     },
     createNode: function (parent, name, mode, dev) {
diff --git a/src/library_pthread_stub.js b/src/library_pthread_stub.js
index 3d47b3c404d24..0a3749d0edcd4 100644
--- a/src/library_pthread_stub.js
+++ b/src/library_pthread_stub.js
@@ -163,23 +163,15 @@ var LibraryPThreadStub = {
   emscripten_main_browser_thread_id: function() { return _pthread_self(); },
 
   // When pthreads is not enabled, we can't use the Atomics futex api to do proper sleeps, so simulate a busy spin wait loop instead.
+  usleep__deps: ['emscripten_get_now'],
   usleep: function(useconds) {
     // int usleep(useconds_t useconds);
     // http://pubs.opengroup.org/onlinepubs/000095399/functions/usleep.html
     // We're single-threaded, so use a busy loop. Super-ugly.
-    var msec = useconds / 1000;
-    if ((ENVIRONMENT_IS_WEB || ENVIRONMENT_IS_WORKER) && self['performance'] && self['performance']['now']) {
-      var start = self['performance']['now']();
-      while (self['performance']['now']() - start < msec) {
-        // Do nothing.
-      }
-    } else {
-      var start = Date.now();
-      while (Date.now() - start < msec) {
-        // Do nothing.
-      }
+    var start = _emscripten_get_now();
+    while (_emscripten_get_now() - start < useconds / 1000) {
+      // Do nothing.
     }
-    return 0;
   },
 
   nanosleep__deps: ['usleep', '__setErrNo'],
diff --git a/src/library_strings.js b/src/library_strings.js
index 6fa0580cf0c1d..277946107901c 100644
--- a/src/library_strings.js
+++ b/src/library_strings.js
@@ -1,6 +1,7 @@
 #if MINIMAL_RUNTIME
 
 #include "runtime_strings_extra.js"
+#include "arrayUtils.js"
 
 mergeInto(LibraryManager.library, {
   $AsciiToString: AsciiToString,
@@ -15,7 +16,9 @@ mergeInto(LibraryManager.library, {
   $allocateUTF8OnStack: allocateUTF8OnStack,
   $writeStringToMemory: writeStringToMemory,
   $writeArrayToMemory: writeArrayToMemory,
-  $writeAsciiToMemory: writeAsciiToMemory
+  $writeAsciiToMemory: writeAsciiToMemory,
+  $intArrayFromString: intArrayFromString,
+  $intArrayToString: intArrayToString
 });
 
 #endif
diff --git a/src/library_syscall.js b/src/library_syscall.js
index d3b1a419688e4..cd46418ca1396 100644
--- a/src/library_syscall.js
+++ b/src/library_syscall.js
@@ -743,6 +743,9 @@ var SyscallsLibrary = {
   __syscall121: function(which, varargs) { // setdomainname
     return -{{{ cDefine('EPERM') }}};
   },
+#if MINIMAL_RUNTIME
+  __syscall122__deps: ['$writeAsciiToMemory'],
+#endif
   __syscall122: function(which, varargs) { // uname
     var buf = SYSCALLS.get();
     if (!buf) return -{{{ cDefine('EFAULT') }}}
diff --git a/src/library_wasi.js b/src/library_wasi.js
index 70632d115e2fb..6084d841ca7dd 100644
--- a/src/library_wasi.js
+++ b/src/library_wasi.js
@@ -11,7 +11,7 @@ var WasiLibrary = {
     return _exit(code);
   },
 
-  emscripten_get_environ__deps: ['$ENV'],
+  emscripten_get_environ__deps: ['$ENV', '_get_executable_name'],
   emscripten_get_environ: function() {
     if (!_emscripten_get_environ.strings) {
       // Default values.
@@ -23,7 +23,7 @@ var WasiLibrary = {
         'HOME': '/home/web_user',
         // Browser language detection #8751
         'LANG': ((typeof navigator === 'object' && navigator.languages && navigator.languages[0]) || 'C').replace('-', '_') + '.UTF-8',
-        '_': thisProgram
+        '_': __get_executable_name()
       };
       // Apply the user-provided values, if any.
       for (var x in ENV) {
@@ -50,7 +50,11 @@ var WasiLibrary = {
     return 0;
   },
 
-  environ_get__deps: ['emscripten_get_environ'],
+  environ_get__deps: ['emscripten_get_environ'
+#if MINIMAL_RUNTIME
+    , '$writeAsciiToMemory'
+#endif
+  ],
   environ_get: function(__environ, environ_buf) {
     var strings = _emscripten_get_environ();
     var bufSize = 0;
diff --git a/src/modules.js b/src/modules.js
index 964746c1e4a00..129ce4db4fc83 100644
--- a/src/modules.js
+++ b/src/modules.js
@@ -376,21 +376,11 @@ function exportRuntime() {
     'getValue',
     'allocate',
     'getMemory',
-    'AsciiToString',
-    'stringToAscii',
     'UTF8ArrayToString',
     'UTF8ToString',
     'stringToUTF8Array',
     'stringToUTF8',
     'lengthBytesUTF8',
-    'UTF16ToString',
-    'stringToUTF16',
-    'lengthBytesUTF16',
-    'UTF32ToString',
-    'stringToUTF32',
-    'lengthBytesUTF32',
-    'allocateUTF8',
-    'allocateUTF8OnStack',
     'stackTrace',
     'addOnPreRun',
     'addOnInit',
@@ -436,10 +426,24 @@ function exportRuntime() {
   ];
 
   if (!MINIMAL_RUNTIME) {
-    runtimeElements.push('warnOnce');
-    runtimeElements.push('stackSave');
-    runtimeElements.push('stackRestore');
-    runtimeElements.push('stackAlloc');
+    // MINIMAL_RUNTIME has moved these functions to library_strings.js
+    runtimeElements = runtimeElements.concat([
+      'warnOnce',
+      'stackSave',
+      'stackRestore',
+      'stackAlloc',
+      'AsciiToString',
+      'stringToAscii',
+      'UTF16ToString',
+      'stringToUTF16',
+      'lengthBytesUTF16',
+      'UTF32ToString',
+      'stringToUTF32',
+      'lengthBytesUTF32',
+      'allocateUTF8',
+      'allocateUTF8OnStack'
+    ]);
+
     if (USE_PTHREADS) {
       runtimeElements.push('establishStackSpace');
     }
diff --git a/src/settings.js b/src/settings.js
index d09f24b31f9fd..01cacd4d81a45 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -1626,7 +1626,7 @@ var SUPPORT_ERRNO = 1;
 // opts are quite hacky, and work around limitations in Closure and other parts
 // of the build system, so they may not work in all generated programs (But can
 // be useful for really small programs)
-var MINIMAL_RUNTIME = 0;
+var MINIMAL_RUNTIME = 1;
 
 // If set to 1, MINIMAL_RUNTIME will utilize streaming WebAssembly compilation,
 // where WebAssembly module is compiled already while it is being downloaded.

From 91e900841de79151a8c1c704bcc654cc5710a2f2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 28 Jan 2020 19:58:53 +0200
Subject: [PATCH 04/17] More core test suite working in MINIMAL_RUNTIME.

---
 emcc.py                  |  5 +++--
 src/library.js           |  4 ++--
 src/library_html5.js     |  2 +-
 src/library_syscall.js   |  7 +++----
 src/postamble_minimal.js | 16 ++++++++++++++++
 src/preamble_minimal.js  | 25 +++++++++++++++++++++++++
 tests/test_core.py       | 32 +++++++++++++++++++++++++++-----
 tests/utf32.cpp          | 16 ++++++++--------
 tests/utf8.cpp           | 26 +++++++++++++-------------
 9 files changed, 98 insertions(+), 35 deletions(-)

diff --git a/emcc.py b/emcc.py
index 4ba8a6b9c3583..a9c5c0fc44023 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1250,8 +1250,9 @@ def is_supported_link_flag(f):
     link_flags = [f for f in link_flags if is_supported_link_flag(f[1])]
 
     if shared.Settings.MINIMAL_RUNTIME:
-      # Remove the default exported functions 'memcpy', 'memset', 'malloc', 'free', etc. - those should only be linked in if used
-      shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE = []
+      # Remove the default exported functions 'malloc', 'free' - those should only be linked in if used
+      for to_remove in ['malloc', 'free']:
+        shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
 
     if shared.Settings.STACK_OVERFLOW_CHECK:
       if shared.Settings.MINIMAL_RUNTIME:
diff --git a/src/library.js b/src/library.js
index 6af32cc831f9e..f2f8494c65ab4 100644
--- a/src/library.js
+++ b/src/library.js
@@ -703,7 +703,7 @@ LibraryManager.library = {
     _exit(-1234);
   },
 
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !EXIT_RUNTIME
   atexit: function(){},
   __cxa_atexit: function(){},
   __cxa_thread_atexit: function(){},
@@ -2163,7 +2163,7 @@ LibraryManager.library = {
   //       compact to do it in JS.
   strftime__deps: ['_isLeapYear', '_arraySum', '_addDays', '_MONTH_DAYS_REGULAR', '_MONTH_DAYS_LEAP'
 #if MINIMAL_RUNTIME
-    , '$intArrayFromString'
+    , '$intArrayFromString', '$writeArrayToMemory'
 #endif
   ],
   strftime: function(s, maxsize, format, tm) {
diff --git a/src/library_html5.js b/src/library_html5.js
index dfe96d7378c59..5ff82e72e9612 100644
--- a/src/library_html5.js
+++ b/src/library_html5.js
@@ -41,7 +41,7 @@ var LibraryJSEvents = {
 #endif
     },
 
-#if !MINIMAL_RUNTIME // In minimal runtime, there is no concept of the page running vs being closed, and hence __ATEXIT__ is not present
+#if !MINIMAL_RUNTIME || EXIT_RUNTIME // In minimal runtime, there is no concept of the page running vs being closed, and hence __ATEXIT__ is not present
     registerRemoveEventListeners: function() {
       if (!JSEvents.removeEventListenersRegistered) {
         __ATEXIT__.push(JSEvents.removeAllEventListeners);
diff --git a/src/library_syscall.js b/src/library_syscall.js
index cd46418ca1396..4348d4a4adfcf 100644
--- a/src/library_syscall.js
+++ b/src/library_syscall.js
@@ -1364,17 +1364,16 @@ var SyscallsLibrary = {
   // This is the set of syscalls that use the FS etc. APIs. The rest is in
   // library_wasi.js.
 
-#if SYSCALLS_REQUIRE_FILESYSTEM == 0
+#if SYSCALLS_REQUIRE_FILESYSTEM == 0 && (!MINIMAL_RUNTIME || EXIT_RUNTIME)
   $flush_NO_FILESYSTEM: function() {
     // flush anything remaining in the buffers during shutdown
-    var fflush = Module["_fflush"];
-    if (fflush) fflush(0);
+    if (typeof _fflush !== 'undefined') _fflush(0);
     var buffers = SYSCALLS.buffers;
     if (buffers[1].length) SYSCALLS.printChar(1, {{{ charCode("\n") }}});
     if (buffers[2].length) SYSCALLS.printChar(2, {{{ charCode("\n") }}});
   },
   fd_write__deps: ['$flush_NO_FILESYSTEM'],
-#if EXIT_RUNTIME == 1 && !MINIMAL_RUNTIME // MINIMAL_RUNTIME does not have __ATEXIT__ (so it does not get flushed stdout at program exit - programs in MINIMAL_RUNTIME do not have a concept of exiting)
+#if EXIT_RUNTIME == 1
   fd_write__postset: '__ATEXIT__.push(flush_NO_FILESYSTEM);',
 #endif
 #endif
diff --git a/src/postamble_minimal.js b/src/postamble_minimal.js
index c21811c3fa02e..049c9f55b493b 100644
--- a/src/postamble_minimal.js
+++ b/src/postamble_minimal.js
@@ -14,6 +14,22 @@ function run() {
     var ret = _proxy_main();
 #else
     var ret = _main();
+
+#if EXIT_RUNTIME
+    callRuntimeCallbacks(__ATEXIT__);
+    {{{ getQuoted('ATEXITS') }}}
+#endif
+
+#if FILESYSTEM && (ASSERTIONS || IN_TEST_HARNESS)
+    // fflush() filesystem stdio for test harness. For production use, instead print full lines to avoid this kind of
+    // lazy behavior.
+    _fflush();
+#endif
+
+#if ASSERTIONS
+    runtimeExited = true;
+#endif
+
 #endif
 
 #if STACK_OVERFLOW_CHECK
diff --git a/src/preamble_minimal.js b/src/preamble_minimal.js
index 2420615b652fd..2b2f5b4ac53df 100644
--- a/src/preamble_minimal.js
+++ b/src/preamble_minimal.js
@@ -185,6 +185,31 @@ var wasmOffsetConverter;
 #include "wasm_offset_converter.js"
 #endif
 
+#if EXIT_RUNTIME
+
+function callRuntimeCallbacks(callbacks) {
+  while(callbacks.length > 0) {
+    var callback = callbacks.shift();
+    if (typeof callback == 'function') {
+      callback();
+      continue;
+    }
+    var func = callback.func;
+    if (typeof func === 'number') {
+      if (callback.arg === undefined) {
+        dynCall_v(func);
+      } else {
+        dynCall_vi(func, callback.arg);
+      }
+    } else {
+      func(callback.arg === undefined ? null : callback.arg);
+    }
+  }
+}
+
+var __ATEXIT__    = []; // functions called during shutdown
+#endif
+
 #if ASSERTIONS
 var runtimeInitialized = false;
 
diff --git a/tests/test_core.py b/tests/test_core.py
index 2e8b667d449f2..4a335febb1102 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -233,6 +233,20 @@ def decorated(self, *args, **kwargs):
   return decorator
 
 
+def no_minimal_runtime(note):
+  assert not callable(note)
+
+  def decorator(f):
+    assert callable(f)
+
+    @wraps(f)
+    def decorated(self, *args, **kwargs):
+      if 'MINIMAL_RUNTIME=1' in self.emcc_args or self.get_setting('MINIMAL_RUNTIME'):
+        self.skipTest(note)
+      f(self, *args, **kwargs)
+    return decorated
+  return decorator
+
 class TestCoreBase(RunnerCore):
   def is_wasm2js(self):
     return self.is_wasm_backend() and not self.get_setting('WASM')
@@ -1971,7 +1985,7 @@ def test_em_asm_arguments_side_effects(self):
   def test_em_js(self, args):
     if 'MAIN_MODULE' in args and self.get_setting('WASM') == 0:
       self.skipTest('main module support for non-wasm')
-    self.emcc_args += args
+    self.emcc_args += args + ['-s', 'EXPORTED_FUNCTIONS=["_main","_malloc"]']
     self.do_run_in_out_file_test('tests', 'core', 'test_em_js')
     self.do_run_in_out_file_test('tests', 'core', 'test_em_js', force_c=True)
 
@@ -5133,20 +5147,27 @@ def test_utime(self):
     src = open(path_from_root('tests', 'utime', 'test_utime.c')).read()
     self.do_run(src, 'success', force_c=True)
 
+  @no_minimal_runtime('MINIMAL_RUNTIME does not have getValue() and setValue() (TODO add it to a JS library function to get it in)')
   def test_utf(self):
     self.banned_js_engines = [SPIDERMONKEY_ENGINE] # only node handles utf well
-    self.set_setting('EXPORTED_FUNCTIONS', ['_main', '_malloc'])
+    self.set_setting('EXPORTED_FUNCTIONS', ['_main', '_malloc',])
     self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['getValue', 'setValue', 'UTF8ToString', 'stringToUTF8'])
     self.do_run_in_out_file_test('tests', 'core', 'test_utf')
 
   def test_utf32(self):
-    self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['UTF32ToString', 'stringToUTF32', 'lengthBytesUTF32'])
+    if self.get_setting('MINIMAL_RUNTIME'):
+      self.set_setting('DEFAULT_LIBRARY_FUNCS_TO_INCLUDE', ['$UTF32ToString', '$stringToUTF32', '$lengthBytesUTF32'])
+    else:
+      self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['UTF32ToString', 'stringToUTF32', 'lengthBytesUTF32'])
     self.do_run(open(path_from_root('tests', 'utf32.cpp')).read(), 'OK.')
     self.do_run(open(path_from_root('tests', 'utf32.cpp')).read(), 'OK.', args=['-fshort-wchar'])
 
   def test_utf8(self):
-    self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS',
-                     ['UTF8ToString', 'stringToUTF8', 'AsciiToString', 'stringToAscii'])
+    if self.get_setting('MINIMAL_RUNTIME'):
+      self.set_setting('DEFAULT_LIBRARY_FUNCS_TO_INCLUDE', ['$AsciiToString', '$stringToAscii', '$writeAsciiToMemory'])
+    else:
+      self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS',
+                      ['UTF8ToString', 'stringToUTF8', 'AsciiToString', 'stringToAscii'])
     self.emcc_args += ['-std=c++11']
     self.do_run(open(path_from_root('tests', 'utf8.cpp')).read(), 'OK.')
 
@@ -6588,6 +6609,7 @@ def test_EXTRA_EXPORTED_RUNTIME_METHODS(self):
     self.do_run_in_out_file_test('tests', 'core', 'EXTRA_EXPORTED_RUNTIME_METHODS')
 
   @no_fastcomp('fails mysteriously on fastcomp (dynCall_viji is not defined); ignored, because fastcomp is deprecated')
+  @no_minimal_runtime('MINIMAL_RUNTIME does not blindly export all symbols to Module to save code size')
   def test_dyncall_specific(self):
     emcc_args = self.emcc_args[:]
     for which, exported_runtime_methods in [
diff --git a/tests/utf32.cpp b/tests/utf32.cpp
index 64674bea03ef6..6acd298a1e529 100644
--- a/tests/utf32.cpp
+++ b/tests/utf32.cpp
@@ -22,9 +22,9 @@ int main() {
 		utf32 *memory = new utf32[wstr.length()+1];
 
 		EM_ASM({
-			var str = Module.UTF32ToString($0);
+			var str = UTF32ToString($0);
 			out(str);
-			var numBytesWritten = Module.stringToUTF32(str, $1, $2);
+			var numBytesWritten = stringToUTF32(str, $1, $2);
 			if (numBytesWritten != 23*4) throw 'stringToUTF32 wrote an invalid length ' + numBytesWritten;
 		}, wstr.c_str(), memory, (wstr.length()+1)*sizeof(utf32));
 
@@ -37,9 +37,9 @@ int main() {
 		}
 
 		EM_ASM({
-			var str = Module.UTF32ToString($0);
+			var str = UTF32ToString($0);
 			out(str);
-			var numBytesWritten = Module.stringToUTF32(str, $1, $2);
+			var numBytesWritten = stringToUTF32(str, $1, $2);
 			if (numBytesWritten != 5*4) throw 'stringToUTF32 wrote an invalid length ' + numBytesWritten;
 		}, wstr.c_str(), memory, 6*sizeof(utf32));
 		assert(memory[5] == 0);
@@ -49,9 +49,9 @@ int main() {
 		utf16 *memory = new utf16[2*wstr.length()+1];
 
 		EM_ASM({
-			var str = Module.UTF16ToString($0);
+			var str = UTF16ToString($0);
 			out(str);
-			var numBytesWritten = Module.stringToUTF16(str, $1, $2);
+			var numBytesWritten = stringToUTF16(str, $1, $2);
 			if (numBytesWritten != 25*2) throw 'stringToUTF16 wrote an invalid length ' + numBytesWritten;
 		}, wstr.c_str(), memory, (2*wstr.length()+1)*sizeof(utf16));
 
@@ -64,9 +64,9 @@ int main() {
 		}
 
 		EM_ASM({
-			var str = Module.UTF16ToString($0);
+			var str = UTF16ToString($0);
 			out(str);
-			var numBytesWritten = Module.stringToUTF16(str, $1, $2);
+			var numBytesWritten = stringToUTF16(str, $1, $2);
 			if (numBytesWritten != 5*2) throw 'stringToUTF16 wrote an invalid length ' + numBytesWritten;
 		}, wstr.c_str(), memory, 6*sizeof(utf16));
 		assert(memory[5] == 0);
diff --git a/tests/utf8.cpp b/tests/utf8.cpp
index ea9335f48f369..fabb1412c6028 100644
--- a/tests/utf8.cpp
+++ b/tests/utf8.cpp
@@ -14,24 +14,24 @@
 int main() {
   const char latin1String[] = "\x26\xA0\xF7";
   EM_ASM({
-    var str = Module.AsciiToString($0);
+    var str = AsciiToString($0);
     assert(str === "\\x26\\xA0\\xF7");
   }, latin1String);
 
   const char asciiString[] = "Hello world!";
   char asciiString2[128] = {};
   EM_ASM({
-    var str = Module.AsciiToString($0);
+    var str = AsciiToString($0);
     out(str);
-    Module.stringToAscii(str, $1);
+    stringToAscii(str, $1);
   }, asciiString, asciiString2);
   assert(!strcmp(asciiString, asciiString2));
 
   char asciiString3[128] = {};
   EM_ASM({
-    var str = Module.UTF8ToString($0);
+    var str = UTF8ToString($0);
     out(str);
-    var numBytesWritten = Module.stringToUTF8(str, $1, $2);
+    var numBytesWritten = stringToUTF8(str, $1, $2);
     if (numBytesWritten != 12) throw 'stringToUTF8 wrote an invalid length ' + numBytesWritten;
   }, asciiString, asciiString3, 128);
   assert(!strcmp(asciiString, asciiString3));
@@ -39,9 +39,9 @@ int main() {
   const char utf8String[] = u8"Hyv\u00E4\u00E4 p\u00E4iv\u00E4\u00E4! T\u00F6\u00F6\u00F6\u00F6t! abc\u2603\u20AC\U0002007C123 --- abc\u2603\u20AC\U0002007C123."; // U+2603 is snowman, U+20AC is the Euro sign, U+2007C is a Chinese Han character that looks like three raindrops.
   char utf8String2[128] = {};
   EM_ASM({
-    var str = Module.UTF8ToString($0);
+    var str = UTF8ToString($0);
     out(str);
-    var numBytesWritten = Module.stringToUTF8(str, $1, $2);
+    var numBytesWritten = stringToUTF8(str, $1, $2);
     if (numBytesWritten != 69) throw 'stringToUTF8 wrote an invalid length ' + numBytesWritten;
   }, utf8String, utf8String2, 128);
   assert(strlen(utf8String) == strlen(utf8String2));
@@ -52,18 +52,18 @@ int main() {
 
   // Test that text gets properly cut off if output buffer is too small.
   EM_ASM({
-    var str = Module.UTF8ToString($0);
+    var str = UTF8ToString($0);
     out(str);
-    var numBytesWritten = Module.stringToUTF8(str, $1, $2);
+    var numBytesWritten = stringToUTF8(str, $1, $2);
     if (numBytesWritten != 9) throw 'stringToUTF8 wrote an invalid length ' + numBytesWritten;
   }, utf8String, utf8String2, 10);
   assert(strlen(utf8String2) == 9);
 
   // Zero-length string.
   EM_ASM({
-    var str = Module.UTF8ToString($0);
+    var str = UTF8ToString($0);
     out(str);
-    var numBytesWritten = Module.stringToUTF8(str, $1, $2);
+    var numBytesWritten = stringToUTF8(str, $1, $2);
     if (numBytesWritten != 0) throw 'stringToUTF8 wrote an invalid length ' + numBytesWritten;
   }, utf8String, utf8String2, 1);
   assert(utf8String2[0] == 0);
@@ -71,9 +71,9 @@ int main() {
   // No bytes output.
   utf8String2[0] = 'X';
   EM_ASM({
-    var str = Module.UTF8ToString($0);
+    var str = UTF8ToString($0);
     out(str);
-    var numBytesWritten = Module.stringToUTF8(str, $1, $2);
+    var numBytesWritten = stringToUTF8(str, $1, $2);
     if (numBytesWritten != 0) throw 'stringToUTF8 wrote an invalid length ' + numBytesWritten;
   }, utf8String, utf8String2, 0);
   assert(utf8String2[0] == 'X');

From 77a59a2b65cb406b3cb0a54fa8a0c1c7886a52b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Thu, 30 Jan 2020 18:50:14 +0200
Subject: [PATCH 05/17] Add missing printf deps in MINIMAL_RUNTIME

---
 src/library_formatString.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/library_formatString.js b/src/library_formatString.js
index bc6bb387a6640..09082d2bc4edb 100644
--- a/src/library_formatString.js
+++ b/src/library_formatString.js
@@ -418,7 +418,11 @@ mergeInto(LibraryManager.library, {
   },
 
   // printf/puts implementations for when musl is not pulled in - very partial. useful for tests, and when bootstrapping structInfo
-  printf__deps: ['_formatString'],
+  printf__deps: ['_formatString'
+#if MINIMAL_RUNTIME
+    , '$intArrayToString'
+#endif
+    ],
   printf: function(format, varargs) {
     // int printf(const char *restrict format, ...);
     // http://pubs.opengroup.org/onlinepubs/000095399/functions/printf.html

From d8c014e29bfec2f26fa7650f406b7bee10d477db Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sat, 1 Feb 2020 20:35:23 +0200
Subject: [PATCH 06/17] Stack functions are not a JS library function in Wasm
 backend.

---
 src/library_html5.js       | 8 ++++----
 src/library_stack_trace.js | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/library_html5.js b/src/library_html5.js
index 5ff82e72e9612..9f36984c3a11e 100644
--- a/src/library_html5.js
+++ b/src/library_html5.js
@@ -175,7 +175,7 @@ var LibraryJSEvents = {
     },
 
 #if USE_PTHREADS
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !WASM_BACKEND
     queueEventHandlerOnThread_iiii__deps: ['$stackSave', '$stackAlloc', '$stackRestore'],
 #endif
     queueEventHandlerOnThread_iiii: function(targetThread, eventHandlerFunc, eventTypeId, eventData, userData) {
@@ -2824,7 +2824,7 @@ var LibraryJSEvents = {
   },
 
   emscripten_set_offscreencanvas_size_on_target_thread_js__deps: ['$stringToNewUTF8'
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !WASM_BACKEND
   , '$stackSave', '$stackAlloc', '$stackRestore'
 #endif
   ],
@@ -2887,7 +2887,7 @@ var LibraryJSEvents = {
 #endif
 
   _set_canvas_element_size__deps: ['emscripten_set_canvas_element_size'
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !WASM_BACKEND
   , '$stackSave', '$stackAlloc', '$stackRestore'
 #endif
   ],
@@ -2964,7 +2964,7 @@ var LibraryJSEvents = {
 
   // JavaScript-friendly API, returns pair [width, height]
   _get_canvas_element_size__deps: ['emscripten_get_canvas_element_size'
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !WASM_BACKEND
   , '$stackSave', '$stackAlloc', '$stackRestore'
 #endif
   ],
diff --git a/src/library_stack_trace.js b/src/library_stack_trace.js
index 8a05fe7d1c9d3..a7ac2850b70f6 100644
--- a/src/library_stack_trace.js
+++ b/src/library_stack_trace.js
@@ -1,7 +1,7 @@
 var LibraryStackTrace = {
 
   $demangle__deps: [
-#if MINIMAL_RUNTIME
+#if MINIMAL_RUNTIME && !WASM_BACKEND
   '$stackSave', '$stackAlloc', '$stackRestore'
 #if ASSERTIONS
     , '$warnOnce'

From 6ef4ad997771a3dfb029d82445297ca5f7737800 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sat, 1 Feb 2020 20:44:00 +0200
Subject: [PATCH 07/17] Cleanup

---
 src/library_syscall.js | 3 ---
 src/settings.js        | 2 +-
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/library_syscall.js b/src/library_syscall.js
index 4348d4a4adfcf..91ea45f33a0d7 100644
--- a/src/library_syscall.js
+++ b/src/library_syscall.js
@@ -227,9 +227,6 @@ var SyscallsLibrary = {
   _emscripten_syscall_mmap2__deps: ['memalign', 'memset', '$SYSCALLS',
 #if FILESYSTEM && SYSCALLS_REQUIRE_FILESYSTEM
     '$FS',
-#endif
-#if MINIMAL_RUNTIME // MINIMAL_RUNTIME does not have a global PAGE_SIZE runtime variable.
-    'getpagesize'
 #endif
   ],
   _emscripten_syscall_mmap2: function(addr, len, prot, flags, fd, off) {
diff --git a/src/settings.js b/src/settings.js
index 01cacd4d81a45..d09f24b31f9fd 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -1626,7 +1626,7 @@ var SUPPORT_ERRNO = 1;
 // opts are quite hacky, and work around limitations in Closure and other parts
 // of the build system, so they may not work in all generated programs (But can
 // be useful for really small programs)
-var MINIMAL_RUNTIME = 1;
+var MINIMAL_RUNTIME = 0;
 
 // If set to 1, MINIMAL_RUNTIME will utilize streaming WebAssembly compilation,
 // where WebAssembly module is compiled already while it is being downloaded.

From 5c7978c9048c9df7713668477fbef5b6d6b03f70 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sat, 1 Feb 2020 20:45:57 +0200
Subject: [PATCH 08/17] cleanup

---
 src/library_syscall.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/library_syscall.js b/src/library_syscall.js
index 91ea45f33a0d7..e147e6e4f1847 100644
--- a/src/library_syscall.js
+++ b/src/library_syscall.js
@@ -230,7 +230,6 @@ var SyscallsLibrary = {
 #endif
   ],
   _emscripten_syscall_mmap2: function(addr, len, prot, flags, fd, off) {
-#endif
     off <<= 12; // undo pgoffset
     var ptr;
     var allocated = false;

From 0f958f4172bf57221fffacbd5f02a7e775f8d166 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sat, 1 Feb 2020 21:17:47 +0200
Subject: [PATCH 09/17] assert() behind ASSERTIONS.

---
 src/Fetch.js                | 2 ++
 src/library_formatString.js | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/src/Fetch.js b/src/Fetch.js
index 1b9361d60284b..26184d0158852 100644
--- a/src/Fetch.js
+++ b/src/Fetch.js
@@ -325,7 +325,9 @@ function __emscripten_fetch_xhr(fetch, onsuccess, onerror, onprogress, onreadyst
   xhr.open(requestMethod, url_, !fetchAttrSynchronous, userNameStr, passwordStr);
   if (!fetchAttrSynchronous) xhr.timeout = timeoutMsecs; // XHR timeout field is only accessible in async XHRs, and must be set after .open() but before .send().
   xhr.url_ = url_; // Save the url for debugging purposes (and for comparing to the responseURL that server side advertised)
+#if ASSERTIONS
   assert(!fetchAttrStreamData, 'streaming uses moz-chunked-arraybuffer which is no longer supported; TODO: rewrite using fetch()');
+#endif
   xhr.responseType = 'arraybuffer';
 
   if (overriddenMimeType) {
diff --git a/src/library_formatString.js b/src/library_formatString.js
index 09082d2bc4edb..5b685237229ec 100644
--- a/src/library_formatString.js
+++ b/src/library_formatString.js
@@ -10,7 +10,9 @@ mergeInto(LibraryManager.library, {
   // Returns the resulting string string as a character array.
   _formatString__deps: ['_reallyNegative'],
   _formatString: function(format, varargs) {
+#if ASSERTIONS
     assert((varargs & 3) === 0);
+#endif
     var textIndex = format;
     var argIndex = varargs;
     // This must be called before reading a double or i64 vararg. It will bump the pointer properly.
@@ -19,11 +21,15 @@ mergeInto(LibraryManager.library, {
       if (type === 'double' || type === 'i64') {
         // move so the load is aligned
         if (ptr & 7) {
+#if ASSERTIONS
           assert((ptr & 7) === 4);
+#endif
           ptr += 4;
         }
       } else {
+#if ASSERTIONS
         assert((ptr & 3) === 0);
+#endif
       }
       return ptr;
     }
@@ -40,7 +46,9 @@ mergeInto(LibraryManager.library, {
                {{{ makeGetValue('argIndex', 4, 'i32', undefined, undefined, true, 4) }}}];
         argIndex += 8;
       } else {
+#if ASSERTIONS
         assert((argIndex & 3) === 0);
+#endif
         type = 'i32'; // varargs are always i32, i64, or double
         ret = {{{ makeGetValue('argIndex', 0, 'i32', undefined, undefined, true) }}};
         argIndex += 4;

From b7ff1d3f14df567546717d2fcb37774a70db790d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Sat, 1 Feb 2020 21:31:04 +0200
Subject: [PATCH 10/17] Fix Closure + Wasm2JS build.

---
 src/promise_polyfill.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/promise_polyfill.js b/src/promise_polyfill.js
index 8ebc4114c30ef..e4e3483ca209b 100644
--- a/src/promise_polyfill.js
+++ b/src/promise_polyfill.js
@@ -23,6 +23,8 @@
 // THE SOFTWARE.
 //==============================================================================
 
+/** @suppress{duplicate} This is already defined in from Closure's built-in
+    externs.zip//es6.js, Closure should not yell when seeing this again. */
 var Promise = (function() {
   function noop() {}
 

From b3eb4828998d1147309b6e5317567e958a2ab115 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Mon, 3 Feb 2020 12:13:26 +0200
Subject: [PATCH 11/17] Flake and fix dladdr

---
 src/library.js     | 2 +-
 tests/test_core.py | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/library.js b/src/library.js
index f2f8494c65ab4..0bfee3500d6c7 100644
--- a/src/library.js
+++ b/src/library.js
@@ -1849,7 +1849,7 @@ LibraryManager.library = {
   dladdr__sig: 'iii',
   dladdr: function(addr, info) {
     // report all function pointers as coming from this program itself XXX not really correct in any way
-    var fname = __get_executable_name(); // XXX leak
+    var fname = stringToNewUTF8(__get_executable_name()); // XXX leak
     {{{ makeSetValue('info', 0, 'fname', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE, '0', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE*2, '0', 'i32') }}};
diff --git a/tests/test_core.py b/tests/test_core.py
index 4a335febb1102..25671ddce7c37 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -247,6 +247,7 @@ def decorated(self, *args, **kwargs):
     return decorated
   return decorator
 
+
 class TestCoreBase(RunnerCore):
   def is_wasm2js(self):
     return self.is_wasm_backend() and not self.get_setting('WASM')
@@ -5150,7 +5151,7 @@ def test_utime(self):
   @no_minimal_runtime('MINIMAL_RUNTIME does not have getValue() and setValue() (TODO add it to a JS library function to get it in)')
   def test_utf(self):
     self.banned_js_engines = [SPIDERMONKEY_ENGINE] # only node handles utf well
-    self.set_setting('EXPORTED_FUNCTIONS', ['_main', '_malloc',])
+    self.set_setting('EXPORTED_FUNCTIONS', ['_main', '_malloc'])
     self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS', ['getValue', 'setValue', 'UTF8ToString', 'stringToUTF8'])
     self.do_run_in_out_file_test('tests', 'core', 'test_utf')
 
@@ -5167,7 +5168,7 @@ def test_utf8(self):
       self.set_setting('DEFAULT_LIBRARY_FUNCS_TO_INCLUDE', ['$AsciiToString', '$stringToAscii', '$writeAsciiToMemory'])
     else:
       self.set_setting('EXTRA_EXPORTED_RUNTIME_METHODS',
-                      ['UTF8ToString', 'stringToUTF8', 'AsciiToString', 'stringToAscii'])
+                       ['UTF8ToString', 'stringToUTF8', 'AsciiToString', 'stringToAscii'])
     self.emcc_args += ['-std=c++11']
     self.do_run(open(path_from_root('tests', 'utf8.cpp')).read(), 'OK.')
 

From 7375c209dffcca253e3414a0795b1a8959b9be6b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Mon, 3 Feb 2020 13:29:43 +0200
Subject: [PATCH 12/17] Revise fflush() behavior in MINIMAL_RUNTIME

---
 src/postamble_minimal.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/postamble_minimal.js b/src/postamble_minimal.js
index 049c9f55b493b..c004eff1c6f41 100644
--- a/src/postamble_minimal.js
+++ b/src/postamble_minimal.js
@@ -20,10 +20,10 @@ function run() {
     {{{ getQuoted('ATEXITS') }}}
 #endif
 
-#if FILESYSTEM && (ASSERTIONS || IN_TEST_HARNESS)
-    // fflush() filesystem stdio for test harness. For production use, instead print full lines to avoid this kind of
-    // lazy behavior.
-    _fflush();
+#if IN_TEST_HARNESS
+    // fflush() filesystem stdio for test harness, since there are existing tests that depend on this behavior.
+    // For production use, instead print full lines to avoid this kind of lazy behavior.
+    if (typeof _fflush !== 'undefined') _fflush();
 #endif
 
 #if ASSERTIONS

From 1ee137238dc82ceda16d6cf83407a19bac47fd1f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Mon, 3 Feb 2020 14:39:24 +0200
Subject: [PATCH 13/17] Drop memcpy and memset by default

---
 emcc.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/emcc.py b/emcc.py
index a9c5c0fc44023..8719b415a4b09 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1250,9 +1250,10 @@ def is_supported_link_flag(f):
     link_flags = [f for f in link_flags if is_supported_link_flag(f[1])]
 
     if shared.Settings.MINIMAL_RUNTIME:
-      # Remove the default exported functions 'malloc', 'free' - those should only be linked in if used
-      for to_remove in ['malloc', 'free']:
-        shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
+      # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
+      for to_remove in ['malloc', 'free', 'memcpy', 'memset']:
+        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
+          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
 
     if shared.Settings.STACK_OVERFLOW_CHECK:
       if shared.Settings.MINIMAL_RUNTIME:

From cb62bc67ec16b35be974131db78ff524f3ccc983 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Mon, 3 Feb 2020 14:49:08 +0200
Subject: [PATCH 14/17] Fix deletion of DEFAULT_LIBRARY_FUNCS_TO_INCLUDE
 exports

---
 emcc.py             | 12 ++++++------
 src/library.js      |  2 +-
 tests/test_other.py | 10 +++++-----
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/emcc.py b/emcc.py
index 8719b415a4b09..5829782aa367b 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1109,6 +1109,12 @@ def get_last_setting_change(setting):
     # Apply -s settings in newargs here (after optimization levels, so they can override them)
     apply_settings(settings_changes)
 
+    if shared.Settings.MINIMAL_RUNTIME or 'MINIMAL_RUNTIME=1' in settings_changes:
+      # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
+      for to_remove in ['malloc', 'free', 'memcpy', 'memset', 'emscripten_get_heap_size']:
+        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
+          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
+
     shared.verify_settings()
 
     def filter_out_dynamic_libs(inputs):
@@ -1249,12 +1255,6 @@ def is_supported_link_flag(f):
 
     link_flags = [f for f in link_flags if is_supported_link_flag(f[1])]
 
-    if shared.Settings.MINIMAL_RUNTIME:
-      # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
-      for to_remove in ['malloc', 'free', 'memcpy', 'memset']:
-        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
-          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
-
     if shared.Settings.STACK_OVERFLOW_CHECK:
       if shared.Settings.MINIMAL_RUNTIME:
         shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += ['$abortStackOverflow']
diff --git a/src/library.js b/src/library.js
index 0bfee3500d6c7..fc1ad6b116d19 100644
--- a/src/library.js
+++ b/src/library.js
@@ -467,7 +467,7 @@ LibraryManager.library = {
   },
 
   emscripten_get_heap_size: function() {
-    return HEAP8.length;
+    return HEAPU8.length;
   },
 
   emscripten_get_sbrk_ptr__asm: true,
diff --git a/tests/test_other.py b/tests/test_other.py
index c75c4db0d4869..2a3cd2e76ed67 100644
--- a/tests/test_other.py
+++ b/tests/test_other.py
@@ -9624,11 +9624,11 @@ def test_minimal_runtime_code_size(self):
       ]
     else:
       test_cases = [
-        (asmjs + opts, hello_world_sources, {'a.html': 1223, 'a.js': 289, 'a.asm.js': 113, 'a.mem': 6}),
-        (opts, hello_world_sources, {'a.html': 1205, 'a.js': 633, 'a.wasm': 86}),
-        (asmjs + opts, hello_webgl_sources, {'a.html': 1353, 'a.js': 4921, 'a.asm.js': 11129, 'a.mem': 321}),
-        (opts, hello_webgl_sources, {'a.html': 1335, 'a.js': 4874, 'a.wasm': 8932}),
-        (opts, hello_webgl2_sources, {'a.html': 1335, 'a.js': 5361, 'a.wasm': 8932}) # Compare how WebGL2 sizes stack up with WebGL 1
+        (asmjs + opts, hello_world_sources, {'a.html': 1222, 'a.js': 289, 'a.asm.js': 113, 'a.mem': 6}),
+        (opts, hello_world_sources, {'a.html': 1204, 'a.js': 630, 'a.wasm': 86}),
+        (asmjs + opts, hello_webgl_sources, {'a.html': 1352, 'a.js': 4896, 'a.asm.js': 11129, 'a.mem': 321}),
+        (opts, hello_webgl_sources, {'a.html': 1334, 'a.js': 4850, 'a.wasm': 8932}),
+        (opts, hello_webgl2_sources, {'a.html': 1334, 'a.js': 5357, 'a.wasm': 8932}) # Compare how WebGL2 sizes stack up with WebGL 1
       ]
 
     success = True

From f46a99537e7f9c02e104103deabc112c4167808d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 4 Feb 2020 19:23:51 +0200
Subject: [PATCH 15/17] Fix location of MINIMAL_RUNTIME reading

---
 emcc.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/emcc.py b/emcc.py
index 5829782aa367b..9a36b1aaf1c18 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1103,18 +1103,18 @@ def get_last_setting_change(setting):
     if 'WARN_ON_UNDEFINED_SYMBOLS=0' in settings_changes:
       shared.Settings.ERROR_ON_UNDEFINED_SYMBOLS = 0
 
+    if shared.Settings.MINIMAL_RUNTIME or 'MINIMAL_RUNTIME=1' in settings_changes or 'MINIMAL_RUNTIME=2' in settings_changes:
+      # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
+      for to_remove in ['malloc', 'free', 'memcpy', 'memset', 'emscripten_get_heap_size']:
+        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
+          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
+
     # Set ASM_JS default here so that we can override it from the command line.
     shared.Settings.ASM_JS = 1 if options.opt_level > 0 else 2
 
     # Apply -s settings in newargs here (after optimization levels, so they can override them)
     apply_settings(settings_changes)
 
-    if shared.Settings.MINIMAL_RUNTIME or 'MINIMAL_RUNTIME=1' in settings_changes:
-      # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
-      for to_remove in ['malloc', 'free', 'memcpy', 'memset', 'emscripten_get_heap_size']:
-        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
-          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
-
     shared.verify_settings()
 
     def filter_out_dynamic_libs(inputs):

From 50dea26a99d6e4432c1aa15e3fe6889bb077fe0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Tue, 4 Feb 2020 19:26:23 +0200
Subject: [PATCH 16/17] Clear DEFAULT_LIBRARY_FUNCS_TO_INCLUDE for
 MINIMAL_RUNTIME

---
 emcc.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/emcc.py b/emcc.py
index 9a36b1aaf1c18..6bf4d260f7985 100755
--- a/emcc.py
+++ b/emcc.py
@@ -1105,9 +1105,7 @@ def get_last_setting_change(setting):
 
     if shared.Settings.MINIMAL_RUNTIME or 'MINIMAL_RUNTIME=1' in settings_changes or 'MINIMAL_RUNTIME=2' in settings_changes:
       # Remove the default exported functions 'malloc', 'free', etc. those should only be linked in if used
-      for to_remove in ['malloc', 'free', 'memcpy', 'memset', 'emscripten_get_heap_size']:
-        if to_remove in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
-          shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.remove(to_remove)
+      shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE = []
 
     # Set ASM_JS default here so that we can override it from the command line.
     shared.Settings.ASM_JS = 1 if options.opt_level > 0 else 2

From ce20cb4c55da63e2a51e8d563cb300fc0a759289 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jukka=20Jyl=C3=A4nki?= <jujjyl@gmail.com>
Date: Thu, 6 Feb 2020 16:39:30 +0200
Subject: [PATCH 17/17] Rename _get_executable_name to _getExecutableName.

---
 src/library.js      | 10 +++++-----
 src/library_wasi.js |  4 ++--
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/library.js b/src/library.js
index fc1ad6b116d19..6aadf579f55a0 100644
--- a/src/library.js
+++ b/src/library.js
@@ -746,7 +746,7 @@ LibraryManager.library = {
   // to limitations in the system libraries (we can't easily add a global
   // ctor to create the environment without it always being linked in with
   // libc).
-  __buildEnvironment__deps: ['$ENV', '_get_executable_name'],
+  __buildEnvironment__deps: ['$ENV', '_getExecutableName'],
   __buildEnvironment: function(environ) {
     // WARNING: Arbitrary limit!
     var MAX_ENV_VALUES = 64;
@@ -765,7 +765,7 @@ LibraryManager.library = {
       ENV['HOME'] = '/home/web_user';
       // Browser language detection #8751
       ENV['LANG'] = ((typeof navigator === 'object' && navigator.languages && navigator.languages[0]) || 'C').replace('-', '_') + '.UTF-8';
-      ENV['_'] = __get_executable_name();
+      ENV['_'] = __getExecutableName();
       // Allocate memory.
 #if !MINIMAL_RUNTIME // TODO: environment support in MINIMAL_RUNTIME
       poolPtr = getMemory(TOTAL_ENV_SIZE);
@@ -1844,12 +1844,12 @@ LibraryManager.library = {
     }
   },
 
-  dladdr__deps: ['$stringToNewUTF8', '_get_executable_name'],
+  dladdr__deps: ['$stringToNewUTF8', '_getExecutableName'],
   dladdr__proxy: 'sync',
   dladdr__sig: 'iii',
   dladdr: function(addr, info) {
     // report all function pointers as coming from this program itself XXX not really correct in any way
-    var fname = stringToNewUTF8(__get_executable_name()); // XXX leak
+    var fname = stringToNewUTF8(__getExecutableName()); // XXX leak
     {{{ makeSetValue('info', 0, 'fname', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE, '0', 'i32') }}};
     {{{ makeSetValue('info', Runtime.QUANTUM_SIZE*2, '0', 'i32') }}};
@@ -5161,7 +5161,7 @@ LibraryManager.library = {
     abort('stack overflow')
   },
 
-  _get_executable_name: function() {
+  _getExecutableName: function() {
 #if MINIMAL_RUNTIME // MINIMAL_RUNTIME does not have a global runtime variable thisProgram
 #if ENVIRONMENT_MAY_BE_NODE
     if (ENVIRONMENT_IS_NODE && process['argv'].length > 1) {
diff --git a/src/library_wasi.js b/src/library_wasi.js
index 6084d841ca7dd..d62581292594e 100644
--- a/src/library_wasi.js
+++ b/src/library_wasi.js
@@ -11,7 +11,7 @@ var WasiLibrary = {
     return _exit(code);
   },
 
-  emscripten_get_environ__deps: ['$ENV', '_get_executable_name'],
+  emscripten_get_environ__deps: ['$ENV', '_getExecutableName'],
   emscripten_get_environ: function() {
     if (!_emscripten_get_environ.strings) {
       // Default values.
@@ -23,7 +23,7 @@ var WasiLibrary = {
         'HOME': '/home/web_user',
         // Browser language detection #8751
         'LANG': ((typeof navigator === 'object' && navigator.languages && navigator.languages[0]) || 'C').replace('-', '_') + '.UTF-8',
-        '_': __get_executable_name()
+        '_': __getExecutableName()
       };
       // Apply the user-provided values, if any.
       for (var x in ENV) {