Merge branch 'link_exports' of github.com:ncbray/emscripten into incoming

3 files changed, 38 insertions, 1 deletions

diff --git a/AUTHORS b/AUTHORS
index d3cdd156..5161f7ad 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -92,4 +92,5 @@ a license to everyone to use it as detailed in LICENSE.)
 * Michael Lelli <toadking@toadking.com>
 * Yu Kobayashi <yukoba@accelart.jp>
 * Pin Zhang <zhangpin04@gmail.com>
+* Nick Bray <ncbray@chromium.org> (copyright owned by Google, Inc.)
 
diff --git a/tests/runner.py b/tests/runner.py
index 54a7a340..14de2db0 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -11685,6 +11685,39 @@ int main(int argc, char const *argv[])
 
       self.assertContained('a\nb\n', run_js(os.path.join(self.get_dir(), 'a.out.js')))
 
+    def test_export_in_a(self):
+      export_name = 'this_is_an_entry_point'
+
+      open('export.c', 'w').write(r'''
+        #include <stdio.h>
+        void %s(void) {
+          printf("Hello, world!\n");
+        }
+      ''' % export_name)
+      Popen([PYTHON, EMCC, 'export.c', '-c', '-o', 'export.o']).communicate()
+      Popen([PYTHON, EMAR, 'rc', 'libexport.a', 'export.o']).communicate()
+
+      open('main.c', 'w').write(r'''
+        int main() {
+          return 0;
+        }
+      ''')
+
+      definition = 'function _%s(' % export_name
+
+      # Sanity check: the symbol should not be linked in if not requested.
+      Popen([PYTHON, EMCC, 'main.c', '-L.', '-lexport']).communicate()
+      self.assertNotContained(definition, open(os.path.join(self.get_dir(), 'a.out.js')).read())
+
+      # Sanity check: exporting without a definition does not cause it to appear.
+      # Note: exporting main prevents emcc from warning that it generated no code.
+      Popen([PYTHON, EMCC, 'main.c', '-s', '''EXPORTED_FUNCTIONS=['_main', '_%s']''' % export_name]).communicate()
+      self.assertNotContained(definition, open(os.path.join(self.get_dir(), 'a.out.js')).read())
+
+      # Actual test: defining symbol in library and exporting it causes it to appear in the output.
+      Popen([PYTHON, EMCC, 'main.c', '-L.', '-lexport', '-s', '''EXPORTED_FUNCTIONS=['_%s']''' % export_name]).communicate()
+      self.assertContained(definition, open(os.path.join(self.get_dir(), 'a.out.js')).read())
+
     def test_embed_file(self):
       open(os.path.join(self.get_dir(), 'somefile.txt'), 'w').write('''hello from a file with lots of data and stuff in it thank you very much''')
       open(os.path.join(self.get_dir(), 'main.cpp'), 'w').write(r'''
diff --git a/tools/shared.py b/tools/shared.py
index c0df227d..b80d9389 100644
--- a/tools/shared.py
+++ b/tools/shared.py
@@ -876,7 +876,10 @@ set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)''' % { 'winfix': '' if not WINDOWS e
   @staticmethod
   def link(files, target, force_archive_contents=False):
     actual_files = []
-    unresolved_symbols = set(['main']) # tracking unresolveds is necessary for .a linking, see below. (and main is always a necessary symbol)
+    # Tracking unresolveds is necessary for .a linking, see below.
+    # Specify all possible entry points to seed the linking process.
+    # For a simple application, this would just be "main".
+    unresolved_symbols = set([func[1:] for func in Settings.EXPORTED_FUNCTIONS])
     resolved_symbols = set()
     temp_dirs = []
     files = map(os.path.abspath, files)