Add a test for handling of multiply defined symbols

tests/runner.py

@@ -919,6 +919,46 @@ if 'benchmark' not in str(sys.argv) and 'sanity' not in str(sys.argv):
         '''
         self.do_run(src, '*1 2*')
 
+    def test_multiply_defined_symbols(self):
+      a1 = "int f() { return 1; }"
+      a1_name = os.path.join(self.get_dir(), 'a1.c')
+      open(a1_name, 'w').write(a1)
+      a2 = "void x() {}"
+      a2_name = os.path.join(self.get_dir(), 'a2.c')
+      open(a2_name, 'w').write(a2)
+      b1 = "int f() { return 2; }"
+      b1_name = os.path.join(self.get_dir(), 'b1.c')
+      open(b1_name, 'w').write(b1)
+      b2 = "void y() {}"
+      b2_name = os.path.join(self.get_dir(), 'b2.c')
+      open(b2_name, 'w').write(b2)
+      main = r'''
+        #include <stdio.h>
+        int f();
+        int main() {
+          printf("result: %d\n", f());
+          return 0;
+        }
+      '''
+      main_name = os.path.join(self.get_dir(), 'main.c')
+      open(main_name, 'w').write(main)
+
+      Building.emcc(a1_name)
+      Building.emcc(a2_name)
+      Building.emcc(b1_name)
+      Building.emcc(b2_name)
+      Building.emcc(main_name)
+
+      liba_name = os.path.join(self.get_dir(), 'liba.a')
+      Building.emar('cr', liba_name, [a1_name + '.o', a2_name + '.o'])
+      libb_name = os.path.join(self.get_dir(), 'libb.a')
+      Building.emar('cr', libb_name, [b1_name + '.o', b2_name + '.o'])
+
+      all_name = os.path.join(self.get_dir(), 'all.bc')
+      Building.link([main_name + '.o', liba_name, libb_name], all_name)
+
+      self.do_ll_run(all_name, 'result: 1')
+
     def test_if(self):
         src = '''
           #include <stdio.h>

tools/shared.py

@@ -546,6 +546,13 @@ set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)'''.replace('$EMSCRIPTEN_ROOT', path_
     Popen([EMCC, filename] + args + ['-o', output_filename], stdout=stdout, stderr=stderr, env=env).communicate()
     assert os.path.exists(output_filename), 'emcc could not create output file'
 
+  @staticmethod
+  def emar(action, output_filename, filenames, stdout=None, stderr=None, env=None):
+    try_delete(output_filename)
+    Popen([EMAR, action, output_filename] + filenames, stdout=stdout, stderr=stderr, env=env).communicate()
+    if 'c' in action:
+      assert os.path.exists(output_filename), 'emar could not create output file'
+
   @staticmethod
   def emscripten(filename, append_ext=True, extra_args=[]):
     # Allow usage of emscripten.py without warning