4 files changed, 24 insertions, 17 deletions
diff --git a/src/wasm-js.cpp b/src/wasm-js.cpp
index c966e07cf..6b5c014c2 100644
--- a/src/wasm-js.cpp
+++ b/src/wasm-js.cpp
@@ -178,25 +178,16 @@ extern "C" double EMSCRIPTEN_KEEPALIVE call_from_js(const char *target) {
   IString name(target);
   assert(instance->functions.find(name) != instance->functions.end());
   Function *function = instance->functions[name];
-  size_t num = EM_ASM_INT_V({ return Module['tempArguments'].length });
-  if (num != function->params.size()) {
-    std::cerr << "warning: bad # of arguments to " << target << ": got " << num << ", but expect " << function->params.size() << '\n';
-    abort(); // TODO: fake missing/extra args?
-#if 0
-    if (num > function->params.size()) {
-      num = function->params.size(); // ignore the rest
-    } else {
-      .. fake missing ..
-    }
-#endif
-  }
+  size_t seen = EM_ASM_INT_V({ return Module['tempArguments'].length });
+  size_t actual = function->params.size();
   ModuleInstance::LiteralList arguments;
-  for (size_t i = 0; i < num; i++) {
+  for (size_t i = 0; i < actual; i++) {
     WasmType type = function->params[i].type;
+    // add the parameter, with a zero value if JS did not provide it.
     if (type == i32) {
-      arguments.push_back(Literal(EM_ASM_INT({ return Module['tempArguments'][$0] }, i)));
+      arguments.push_back(Literal(i < seen ? EM_ASM_INT({ return Module['tempArguments'][$0] }, i) : (int32_t)0));
     } else if (type == f64) {
-      arguments.push_back(Literal(EM_ASM_DOUBLE({ return Module['tempArguments'][$0] }, i)));
+      arguments.push_back(Literal(i < seen ? EM_ASM_DOUBLE({ return Module['tempArguments'][$0] }, i) : (double)0.0));
     } else {
       abort();
     }
diff --git a/test/calls.cpp b/test/calls.cpp
index b73dff3f4..0afb0eb69 100644
--- a/test/calls.cpp
+++ b/test/calls.cpp
@@ -1,5 +1,3 @@
-#include <cmath>
-#include <algorithm>
 #include <emscripten.h>
 
 extern "C" {
@@ -17,5 +15,10 @@ int EMSCRIPTEN_KEEPALIVE fibo(int x) {
   return fibo(x-1) + fibo(x-2);
 }
 
+int EMSCRIPTEN_KEEPALIVE run_script() {
+  emscripten_run_script("Module.print('hello from called script')");
+  return emscripten_run_script_int("1+2+3+4-1");
+}
+
 }
 
diff --git a/test/calls.post.js b/test/calls.post.js
index f2b422ed2..bec4d498b 100644
--- a/test/calls.post.js
+++ b/test/calls.post.js
@@ -14,3 +14,10 @@ function test(name) {
 test('simple');
 test('fibo');
 
+Module.print('run_script');
+Module.print(Module['_run_script']());
+
+Module.print('too many/few arguments');
+Module.print(Module['_simple']());
+Module.print(Module['_simple'](10, 20));
+
diff --git a/test/calls.txt b/test/calls.txt
index 7d1b8ee47..6a175ed04 100644
--- a/test/calls.txt
+++ b/test/calls.txt
@@ -10,3 +10,9 @@ fibo
   3 ==> 3
   4 ==> 5
   7 ==> 21
+run_script
+hello from called script
+9
+too many/few arguments
+2
+102