diff --git a/CHANGES b/CHANGES
index 6e99b978d..d33f5431d 100644
--- a/CHANGES
+++ b/CHANGES
@@ -79,9 +79,15 @@ Deprecated
 Features added
 --------------
 
+* #3926: Add ``autodoc_warningiserror`` to suppress the behavior of ``-W``
+  option during importing target modules on autodoc
+
 Bugs fixed
 ----------
 
+* #3924: docname lost after dynamically parsing RST in extension
+* #3946: Typo in sphinx.sty (this was a bug with no effect in default context)
+
 Testing
 --------
 
diff --git a/doc/ext/autodoc.rst b/doc/ext/autodoc.rst
index 62079c928..1f1892dbf 100644
--- a/doc/ext/autodoc.rst
+++ b/doc/ext/autodoc.rst
@@ -386,6 +386,13 @@ There are also new config values that you can set:
       This config value only requires to declare the top-level modules that
       should be mocked.
 
+.. confval:: autodoc_warningiserror
+
+   This value controls the behavior of :option:`sphinx-build -W` during
+   importing modules.
+   If ``False`` is given, autodoc forcely suppresses the error if the imported
+   module emits warnings.  By default, ``True``.
+
 Docstring preprocessing
 -----------------------
 
diff --git a/doc/extdev/appapi.rst b/doc/extdev/appapi.rst
index a27340d55..ce856d031 100644
--- a/doc/extdev/appapi.rst
+++ b/doc/extdev/appapi.rst
@@ -454,6 +454,28 @@ The application object also provides support for emitting leveled messages.
 .. automethod:: Sphinx.debug2
 
 
+Sphinx runtime information
+--------------------------
+
+The application object also provides runtime information as attributes.
+
+.. attribute:: srcdir
+
+   Source directory.
+
+.. attribute:: confdir
+
+   Directory containing ``conf.py``.
+
+.. attribute:: doctreedir
+
+   Directory for storing pickled doctrees.
+
+.. attribute:: outdir
+
+   Directory for storing built document.
+
+
 .. _events:
 
 Sphinx core events
diff --git a/doc/extdev/envapi.rst b/doc/extdev/envapi.rst
index 729725fc5..442cfde15 100644
--- a/doc/extdev/envapi.rst
+++ b/doc/extdev/envapi.rst
@@ -19,10 +19,6 @@ Build environment API
 
       Source directory.
 
-   .. attribute:: confdir
-
-      Directory containing ``conf.py``.
-
    .. attribute:: doctreedir
 
       Directory for storing pickled doctrees.
diff --git a/sphinx/environment/__init__.py b/sphinx/environment/__init__.py
index c8d3e9c98..53693aaf7 100644
--- a/sphinx/environment/__init__.py
+++ b/sphinx/environment/__init__.py
@@ -18,6 +18,7 @@ import codecs
 import fnmatch
 import warnings
 from os import path
+from copy import copy
 from collections import defaultdict
 
 from six import BytesIO, itervalues, class_types, next
@@ -921,6 +922,7 @@ class BuildEnvironment(object):
         """Apply all post-transforms."""
         try:
             # set env.docname during applying post-transforms
+            backup = copy(self.temp_data)
             self.temp_data['docname'] = docname
 
             transformer = SphinxTransformer(doctree)
@@ -928,7 +930,7 @@ class BuildEnvironment(object):
             transformer.add_transforms(self.app.post_transforms)
             transformer.apply_transforms()
         finally:
-            self.temp_data.clear()
+            self.temp_data = backup
 
         # allow custom references to be resolved
         self.app.emit('doctree-resolved', doctree, docname)
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 2a0013293..967cd9c5a 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -394,7 +394,8 @@ class Documenter(object):
             logger.debug('[autodoc] import %s', self.modname)
             with warnings.catch_warnings():
                 warnings.filterwarnings("ignore", category=ImportWarning)
-                __import__(self.modname)
+                with logging.skip_warningiserror(not self.env.config.autodoc_warningiserror):
+                    __import__(self.modname)
             parent = None
             obj = self.module = sys.modules[self.modname]
             logger.debug('[autodoc] => %r', obj)
@@ -1615,6 +1616,7 @@ def setup(app):
     app.add_config_value('autodoc_default_flags', [], True)
     app.add_config_value('autodoc_docstring_signature', True, True)
     app.add_config_value('autodoc_mock_imports', [], True)
+    app.add_config_value('autodoc_warningiserror', True, True)
     app.add_event('autodoc-process-docstring')
     app.add_event('autodoc-process-signature')
     app.add_event('autodoc-skip-member')
diff --git a/sphinx/texinputs/sphinx.sty b/sphinx/texinputs/sphinx.sty
index 515bc8cce..28f0091ff 100644
--- a/sphinx/texinputs/sphinx.sty
+++ b/sphinx/texinputs/sphinx.sty
@@ -6,7 +6,7 @@
 %
 
 \NeedsTeXFormat{LaTeX2e}[1995/12/01]
-\ProvidesPackage{sphinx}[2017/06/17 v1.6.3 LaTeX package (Sphinx markup)]
+\ProvidesPackage{sphinx}[2017/07/24 v1.6.4 LaTeX package (Sphinx markup)]
 
 % provides \ltx@ifundefined
 % (many packages load ltxcmds: graphicx does for pdftex and lualatex but
@@ -1166,7 +1166,7 @@
 % and there is consequently no corresponding package option
 \definecolor{sphinxnoteBgColor}{rgb}{1,1,1}
 \definecolor{sphinxhintBgColor}{rgb}{1,1,1}
-\definecolor{sphinimportantBgColor}{rgb}{1,1,1}
+\definecolor{sphinximportantBgColor}{rgb}{1,1,1}
 \definecolor{sphinxtipBgColor}{rgb}{1,1,1}
 
 % Others get more distinction
diff --git a/sphinx/util/logging.py b/sphinx/util/logging.py
index 85766a774..04cb5fcab 100644
--- a/sphinx/util/logging.py
+++ b/sphinx/util/logging.py
@@ -249,6 +249,27 @@ def pending_logging():
         memhandler.flushTo(logger)
 
 
+@contextmanager
+def skip_warningiserror(skip=True):
+    # type: (bool) -> Generator
+    """contextmanager to skip WarningIsErrorFilter for a while."""
+    logger = logging.getLogger()
+
+    if skip is False:
+        yield
+    else:
+        try:
+            disabler = DisableWarningIsErrorFilter()
+            for handler in logger.handlers:
+                # use internal method; filters.insert() directly to install disabler
+                # before WarningIsErrorFilter
+                handler.filters.insert(0, disabler)
+            yield
+        finally:
+            for handler in logger.handlers:
+                handler.removeFilter(disabler)
+
+
 class LogCollector(object):
     def __init__(self):
         # type: () -> None
@@ -330,7 +351,10 @@ class WarningIsErrorFilter(logging.Filter):
 
     def filter(self, record):
         # type: (logging.LogRecord) -> bool
-        if self.app.warningiserror:
+        if getattr(record, 'skip_warningsiserror', False):
+            # disabled by DisableWarningIsErrorFilter
+            return True
+        elif self.app.warningiserror:
             location = getattr(record, 'location', '')
             if location:
                 raise SphinxWarning(location + ":" + record.msg % record.args)
@@ -340,6 +364,15 @@ class WarningIsErrorFilter(logging.Filter):
             return True
 
 
+class DisableWarningIsErrorFilter(logging.Filter):
+    """Disable WarningIsErrorFilter if this filter installed."""
+
+    def filter(self, record):
+        # type: (logging.LogRecord) -> bool
+        record.skip_warningsiserror = True  # type: ignore
+        return True
+
+
 class WarningLogRecordTranslator(logging.Filter):
     """Converts a log record to one Sphinx expects
 
diff --git a/tests/test_util_logging.py b/tests/test_util_logging.py
index 7ca7bd655..717aa6cd4 100644
--- a/tests/test_util_logging.py
+++ b/tests/test_util_logging.py
@@ -272,3 +272,27 @@ def test_output_with_unencodable_char(app, status, warning):
     status.seek(0)
     logger.info(u"unicode \u206d...")
     assert status.getvalue() == "unicode ?...\n"
+
+
+def test_skip_warningiserror(app, status, warning):
+    logging.setup(app, status, warning)
+    logger = logging.getLogger(__name__)
+
+    app.warningiserror = True
+    with logging.skip_warningiserror():
+        logger.warning('message')
+
+    # if False, warning raises SphinxWarning exception
+    with pytest.raises(SphinxWarning):
+        with logging.skip_warningiserror(False):
+            logger.warning('message')
+
+    # It also works during pending_warnings.
+    with logging.pending_warnings():
+        with logging.skip_warningiserror():
+            logger.warning('message')
+
+    with pytest.raises(SphinxWarning):
+        with logging.pending_warnings():
+            with logging.skip_warningiserror(False):
+                logger.warning('message')