Enable and improve test_stack_overflow_check

src/postamble.js

@@ -189,10 +189,6 @@ function callMain(args) {
     var start = Date.now();
 #endif
 
-#if STACK_OVERFLOW_CHECK >= 2
-    Module['___set_stack_limit'](STACK_MAX);
-#endif
-
 #if PROXY_TO_PTHREAD
     // User requested the PROXY_TO_PTHREAD option, so call a stub main which pthread_create()s a new thread
     // that will call the user's real main() for the application.

src/postamble_minimal.js

@@ -14,6 +14,10 @@ function run() {
   emscriptenMemoryProfiler.onPreloadComplete();
 #endif
 
+#if STACK_OVERFLOW_CHECK >= 2
+    ___set_stack_limits(STACK_BASE, STACK_MAX);
+#endif
+
 #if PROXY_TO_PTHREAD
     // User requested the PROXY_TO_PTHREAD option, so call a stub main which pthread_create()s a new thread
     // that will call the user's real main() for the application.

src/preamble.js

@@ -482,6 +482,9 @@ function initRuntime() {
   assert(!runtimeInitialized);
 #endif
   runtimeInitialized = true;
+#if STACK_OVERFLOW_CHECK >= 2
+  Module['___set_stack_limits'](STACK_BASE, STACK_MAX);
+#endif
   {{{ getQuoted('ATINITS') }}}
   callRuntimeCallbacks(__ATINIT__);
 }

tests/stack_overflow.cpp

@@ -9,25 +9,30 @@
 
 void __attribute__((noinline)) InteropString(char *staticBuffer)
 {
-	char *string = (char*)EM_ASM_INT({
-		var str = "hello, this is a string! ";
-		for(var i = 0; i < 15; ++i)
-			str = str + str;
-		var stringOnTheStack = allocate(intArrayFromString(str), 'i8', ALLOC_STACK);
-		return stringOnTheStack;
-	});
-
-	int stringLength = strlen(string);
-	printf("Got string: %s\n", string);
-	printf("Received a string of length %d.\n", stringLength);
-	strcpy(staticBuffer, string);
+  char *string = (char*)EM_ASM_INT({
+    var str = "hello, this is a string! ";
+#if ONE_BIG_STRING
+    // double it until it is bigger than the stack
+    for (var i = 0; i < 15; ++i) {
+      str = str + str;
+    }
+    allocate(intArrayFromString(str), "i8", ALLOC_STACK);
+#else
+    // allocate as many times as we need to overflow
+    for (var i = 0; i < 1024 * 1024; i++) {
+      allocate(intArrayFromString(str), "i8", ALLOC_STACK);
+    }
+    abort("we should never get here!");
+#endif
+  });
 }
 
 int main()
 {
-	char staticBuffer[512288] = {}; // Make asm.js side consume a large portion of the stack, before bumping the rest with C++<->JS interop.
-	InteropString(staticBuffer);
-	int stringLength = strlen(staticBuffer);
-	printf("Got string: %s\n", staticBuffer);
-	printf("Received a string of length %d.\n", stringLength);
+  // Make C side consume a large portion of the stack, before bumping the rest with C++<->JS interop.
+  char staticBuffer[512288] = {};
+  InteropString(staticBuffer);
+  int stringLength = strlen(staticBuffer);
+  printf("Got string: %s\n", staticBuffer);
+  printf("Received a string of length %d.\n", stringLength);
 }

tests/test_core.py

@@ -135,7 +135,7 @@ def decorated(self):
 
 def can_do_standalone(self):
   return self.get_setting('WASM') and \
-      not self.get_setting('SAFE_STACK') and \
+      self.get_setting('STACK_OVERFLOW_CHECK') < 2 and \
       not self.get_setting('MINIMAL_RUNTIME') and \
       '-fsanitize=address' not in self.emcc_args
 
@@ -786,6 +786,8 @@ def test_loop(self):
 
   def test_stack(self):
     self.set_setting('INLINING_LIMIT', 50)
+    # some extra coverage in all test suites for stack checks
+    self.set_setting('STACK_OVERFLOW_CHECK', 2)
 
     self.do_run_in_out_file_test('tests', 'core', 'test_stack.c')
 
@@ -7810,15 +7812,13 @@ def test_fs_dict_none(self):
     self.do_run('int main() { return 0; }', expected)
 
   @sync
-  @no_wasm_backend("https://github.com/emscripten-core/emscripten/issues/9039")
   def test_stack_overflow_check(self):
-    args = self.emcc_args + ['-s', 'TOTAL_STACK=1048576']
-
-    self.emcc_args = args + ['-s', 'STACK_OVERFLOW_CHECK=2', '-s', 'ASSERTIONS=0']
-    self.do_runf(path_from_root('tests', 'stack_overflow.cpp'), 'Stack overflow! Attempted to allocate', assert_returncode=NON_ZERO)
+    self.set_setting('TOTAL_STACK', 1048576)
+    self.set_setting('STACK_OVERFLOW_CHECK', 2)
+    self.do_runf(path_from_root('tests', 'stack_overflow.cpp'), 'stack overflow', assert_returncode=NON_ZERO)
 
-    self.emcc_args = args + ['-s', 'ASSERTIONS=1']
-    self.do_runf(path_from_root('tests', 'stack_overflow.cpp'), 'Stack overflow! Attempted to allocate', assert_returncode=NON_ZERO)
+    self.emcc_args += ['-DONE_BIG_STRING']
+    self.do_runf(path_from_root('tests', 'stack_overflow.cpp'), 'stack overflow', assert_returncode=NON_ZERO)
 
   @node_pthreads
   def test_binaryen_2170_emscripten_atomic_cas_u8(self):
@@ -8206,7 +8206,6 @@ def test_safe_stack_alloca(self):
                  expected_output=['abort(stack overflow)', '__handle_stack_overflow'], assert_returncode=NON_ZERO)
 
   @needs_dlfcn
-  @unittest.skip('allow binaryen change to roll in')
   def test_safe_stack_dylink(self):
     self.set_setting('STACK_OVERFLOW_CHECK', 2)
     self.set_setting('TOTAL_STACK', 65536)