Merge pull request #1831 from dinibu/dependency-fix-1820

Further changes for issue #1732

3 files changed, 35 insertions, 2 deletions

diff --git a/emcc b/emcc
index 008468a1..6a483a39 100755
--- a/emcc
+++ b/emcc
@@ -1274,7 +1274,16 @@ try:
         shutil.move(in_temp(unsuffixed(uniquename(input_file)) + '.o'), unsuffixed_basename(input_file) + '.' + final_suffix)
     else:
       if len(input_files) == 1:
-        shutil.move(in_temp(unsuffixed(uniquename(input_files[0])) + '.o'), specified_target)
+        temp_output_base = in_temp(unsuffixed(uniquename(input_files[0])))
+        shutil.move(temp_output_base + '.o', specified_target)
+        if os.path.exists(temp_output_base + '.d'):
+          # There was a .d file generated, from -MD or -MMD and friends, save a copy of it to where the output resides,
+          # adjusting the target name away from the temporary file name to the specified target.
+          # It will be deleted with the rest of the temporary directory.
+          deps = open(temp_output_base + '.d').read()
+          deps = deps.replace(temp_output_base + '.o', specified_target)
+          with open(os.path.join(os.path.dirname(specified_target), os.path.basename(unsuffixed(input_files[0]) + '.d')), "w") as out_dep:
+            out_dep.write(deps)
       else:
         assert len(original_input_files) == 1 or not has_dash_c, 'fatal error: cannot specify -o with -c with multiple files' + str(sys.argv) + ':' + str(original_input_files)
         # We have a specified target (-o <target>), which is not JavaScript or HTML, and
diff --git a/tests/test_other.py b/tests/test_other.py
index 0dd0bd12..1144ec26 100644
--- a/tests/test_other.py
+++ b/tests/test_other.py
@@ -2074,3 +2074,27 @@ int main()
     Popen([PYTHON, EMCC, path_from_root('tests', 'linpack.c'), '-O2', '-DSP', '--llvm-opts', '''['-O3', '-vectorize', '-vectorize-loops', '-bb-vectorize-vector-bits=128', '-force-vector-width=4']''']).communicate()
     self.assertContained('Unrolled Single  Precision', run_js('a.out.js'))
 
+  def test_dependency_file(self):
+    # Issue 1732: -MMD (and friends) create dependency files that need to be
+    # copied from the temporary directory.
+
+    open(os.path.join(self.get_dir(), 'test.cpp'), 'w').write(r'''
+      #include "test.hpp"
+
+      void my_function()
+      {
+      }
+    ''')
+    open(os.path.join(self.get_dir(), 'test.hpp'), 'w').write(r'''
+      void my_function();
+    ''')
+
+    Popen([PYTHON, EMCC, '-MMD', '-c', os.path.join(self.get_dir(), 'test.cpp'), '-o',
+      os.path.join(self.get_dir(), 'test.o')]).communicate()
+
+    assert os.path.exists(os.path.join(self.get_dir(), 'test.d')), 'No dependency file generated'
+    deps = open(os.path.join(self.get_dir(), 'test.d')).read()
+    head, tail = deps.split( ':', 2 )
+    assert 'test.o' in head, 'Invalid dependency target'
+    assert 'test.cpp' in tail and 'test.hpp' in tail, 'Invalid dependencies generated'
+
diff --git a/tools/shared.py b/tools/shared.py
index 0a6740b9..ba476883 100644
--- a/tools/shared.py
+++ b/tools/shared.py
@@ -1029,7 +1029,7 @@ class Building:
               dirname = os.path.dirname(content)
               if dirname and not os.path.exists(dirname):
                 os.makedirs(dirname)
-            Popen([LLVM_AR, 'x', f], stdout=PIPE).communicate() # if absolute paths, files will appear there. otherwise, in this directory
+            Popen([LLVM_AR, 'xo', f], stdout=PIPE).communicate() # if absolute paths, files will appear there. otherwise, in this directory
             contents = map(lambda content: os.path.join(temp_dir, content), contents)
             contents = filter(os.path.exists, map(os.path.abspath, contents))
             added_contents = set()