ERROR_ON_UNRESOLVED_SYMBOLS option

3 files changed, 21 insertions, 1 deletions

diff --git a/src/jsifier.js b/src/jsifier.js
index 045328f8..5fcf6b18 100644
--- a/src/jsifier.js
+++ b/src/jsifier.js
@@ -487,6 +487,7 @@ function JSify(data, functionsOnly, givenFunctions) {
       } else {
         // If this is not linkable, anything not in the library is definitely missing
         if (!LINKABLE && !LibraryManager.library.hasOwnProperty(shortident) && !LibraryManager.library.hasOwnProperty(shortident + '__inline')) {
+          if (ERROR_ON_UNDEFINED_SYMBOLS) error('unresolved symbol: ' + shortident);
           if (VERBOSE || WARN_ON_UNDEFINED_SYMBOLS) printErr('warning: unresolved symbol: ' + shortident);
           LibraryManager.library[shortident] = new Function("Module['printErr']('missing function: " + shortident + "'); abort(-1);");
         }
diff --git a/src/settings.js b/src/settings.js
index c878be92..48b0347e 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -317,6 +317,9 @@ var WARN_ON_UNDEFINED_SYMBOLS = 0; // If set to 1, we will warn on any undefined
                                    // the existing buildsystem), and (2) functions might be
                                    // implemented later on, say in --pre-js
 
+var ERROR_ON_UNDEFINED_SYMBOLS = 0; // If set to 1, we will give a compile-time error on any
+                                    // undefined symbols (see WARN_ON_UNDEFINED_SYMBOLS).
+
 var SMALL_XHR_CHUNKS = 0; // Use small chunk size for binary synchronous XHR's in Web Workers.
                           // Used for testing.
                           // See test_chunked_synchronous_xhr in runner.py and library.js.
diff --git a/tests/runner.py b/tests/runner.py
index 418133a0..008a73f0 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -10230,13 +10230,29 @@ f.close()
         }
       ''')
 
+      def clear(): try_delete('a.out.js')
+
       for args in [[], ['-O2']]:
-        print args
+        clear()
+        print 'warn', args
         output = Popen([PYTHON, EMCC, os.path.join(self.get_dir(), 'main.cpp'), '-s', 'WARN_ON_UNDEFINED_SYMBOLS=1'] + args, stderr=PIPE).communicate()
         self.assertContained('unresolved symbol: something', output[1])
 
+        clear()
+        output = Popen([PYTHON, EMCC, os.path.join(self.get_dir(), 'main.cpp')] + args, stderr=PIPE).communicate()
+        self.assertNotContained('unresolved symbol: something\n', output[1])
+
+      for args in [[], ['-O2']]:
+        clear()
+        print 'error', args
+        output = Popen([PYTHON, EMCC, os.path.join(self.get_dir(), 'main.cpp'), '-s', 'ERROR_ON_UNDEFINED_SYMBOLS=1'] + args, stderr=PIPE).communicate()
+        self.assertContained('unresolved symbol: something', output[1])
+        assert not os.path.exists('a.out.js')
+
+        clear()
         output = Popen([PYTHON, EMCC, os.path.join(self.get_dir(), 'main.cpp')] + args, stderr=PIPE).communicate()
         self.assertNotContained('unresolved symbol: something\n', output[1])
+        assert os.path.exists('a.out.js')
 
     def test_toobig(self):
       open(os.path.join(self.get_dir(), 'main.cpp'), 'w').write(r'''