Repository: sphinx-doc/sphinx

Issue:
lualatex issue: PDF build fails if indexed word starts with Unicode characters

#### Procedure to reproduce the problem

Do ``make latexpdf`` with this index.rst:

```
.. index:: état
```

and  having configured ``latex_engine = 'lualatex'`` in conf.py

#### Error logs / results
```
! String contains an invalid utf-8 sequence.
l.4   \bigletter 
               ?^^@
? 
```

#### Expected results

PDF build succeeds.

It does with `xelatex` but this is luck. In fact, usage of `makeindex` program to create `.ind` file results in a non-valid file for utf-8 encoding. Here is how the file looks like when opened as if latin-1 encoded:

```
\begin{sphinxtheindex}
\def\bigletter#1{{\Large\sffamily#1}\nopagebreak\vspace{1mm}}

  \bigletter Ã
  \item Ã©tat, \hyperpage{1}

\end{sphinxtheindex}
```

Probably `xindy` should be used with `lualatex/xelatex`. But this requires particular set-up.

Relates: https://github.com/sphinx-doc/sphinx/issues/5130#issuecomment-401450137


### Environment info
- OS: Mac
- Python version: 3.6.5
- Sphinx version: 1.7.4


Discussion:

Patch:
diff --git a/CHANGES b/CHANGES
index bfb58cd50..4db799ef4 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,11 @@ Release 1.8.0 (in development)
 Dependencies
 ------------
 
+* LaTeX: :confval:`latex_use_xindy`, if ``True`` (default for
+  ``xelatex/lualatex``), instructs ``make latexpdf`` to use :program:`xindy`
+  for general index.  Make sure your LaTeX distribution includes it.
+  (refs: #5134)
+
 Incompatible changes
 --------------------
 
@@ -39,6 +44,10 @@ Incompatible changes
   Please use ``app.add_js_file()`` instead.
 * #5072: Save environment object also with only new documents
 * #5035: qthelp builder allows dashes in :confval:`qthelp_namespace`
+* LaTeX: with lualatex or xelatex use by default :program:`xindy` as
+  UTF-8 able replacement of :program:`makeindex` (refs: #5134).  After
+  upgrading Sphinx, please clean latex build repertory of existing project
+  before new build.
 
 Deprecated
 ----------
@@ -143,6 +152,8 @@ Features added
   for mathjax
 * #4362: latex: Don't overwrite .tex file if document not changed
 * #1431: latex: Add alphanumeric enumerated list support
+* Add :confval:`latex_use_xindy` for UTF-8 savvy indexing, defaults to ``True``
+  if :confval:`latex_engine` is ``'xelatex'`` or ``'lualatex'``.
 
 Bugs fixed
 ----------
@@ -152,6 +163,7 @@ Bugs fixed
 * #4945: i18n: fix lang_COUNTRY not fallback correctly for IndexBuilder. Thanks
   to Shengjing Zhu.
 * #4983: productionlist directive generates invalid IDs for the tokens
+* #5132: (lualatex) PDF build fails if indexed word starts with Unicode character
 * #5133: latex: index headings "Symbols" and "Numbers" not internationalized
 
 Testing
diff --git a/doc/conf.py b/doc/conf.py
index 732c4d4a0..724d355d0 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -72,6 +72,7 @@
 ''',
 }
 latex_show_urls = 'footnote'
+latex_use_xindy = True
 
 autodoc_member_order = 'groupwise'
 todo_include_todos = True
diff --git a/doc/usage/configuration.rst b/doc/usage/configuration.rst
index a0fbe641a..8db606515 100644
--- a/doc/usage/configuration.rst
+++ b/doc/usage/configuration.rst
@@ -1872,6 +1872,40 @@ information.
 
    .. versionadded:: 1.6
 
+.. confval:: latex_use_xindy
+
+   If ``True``, the PDF build from the LaTeX files created by Sphinx
+   will use :program:`xindy` (doc__) rather than :program:`makeindex`
+   for preparing the index of general terms (from :rst:dir:`index`
+   usage).  This means that words with UTF-8 characters will get
+   ordered correctly for the :confval:`language`.
+
+   __ http://xindy.sourceforge.net/
+
+   - This option is ignored if :confval:`latex_engine` is ``'platex'``
+     (Japanese documents) as :program:`mendex` is used in that case.
+
+   - The default is ``True`` for ``'xelatex'`` or ``'lualatex'`` as
+     :program:`makeindex`, if any indexed term starts with a non-ascii
+     character, creates ``.ind`` file containing invalid bytes for
+     UTF-8 encoding. With ``'lualatex'`` this then breaks the PDF
+     build.  Notice that :program:`xindy` supports most but not
+     all European languages.
+
+   - The default is ``False`` for ``'pdflatex'`` but ``True`` is
+     recommended for non-English documents as soon as some indexed
+     terms use non-ascii characters from the language script.
+     Cyrillic scripts are (transparently) supported with
+     ``'pdflatex'`` thanks to a specific Sphinx-contributed ``xindy``
+     style file :file:`cyrLICRutf8.xdy`.
+
+     As :program:`xindy` does not support the same range of languages
+     as ``LaTeX/babel`` does, the default :program:`makeindex` for
+     ``'pdflatex'`` may be preferred in some circumstances, although
+     the index will be ill-formed probably.
+
+   .. versionadded:: 1.8
+
 .. confval:: latex_elements
 
    .. versionadded:: 0.5
diff --git a/sphinx/builders/latex/__init__.py b/sphinx/builders/latex/__init__.py
index 382914731..c17ead5c2 100644
--- a/sphinx/builders/latex/__init__.py
+++ b/sphinx/builders/latex/__init__.py
@@ -44,6 +44,67 @@
     from sphinx.config import Config  # NOQA
 
 
+XINDY_LANG_OPTIONS = {
+    # language codes from docutils.writers.latex2e.Babel
+    # ! xindy language names may differ from those in use by LaTeX/babel
+    # ! xindy does not support all Latin scripts as recognized by LaTeX/babel
+    # ! not all xindy-supported languages appear in Babel.language_codes
+    # cd /usr/local/texlive/2018/texmf-dist/xindy/modules/lang
+    # find . -name '*utf8.xdy'
+    # LATIN
+    'sq': '-L albanian -C utf8 ',
+    'hr': '-L croatian -C utf8 ',
+    'cs': '-L czech -C utf8 ',
+    'da': '-L danish -C utf8 ',
+    'nl': '-L dutch -C ij-as-ij-utf8 ',
+    'en': '-L english -C utf8 ',
+    'eo': '-L esperanto -C utf8 ',
+    'et': '-L estonian -C utf8 ',
+    'fi': '-L finnish -C utf8 ',
+    'fr': '-L french -C utf8 ',
+    'de': '-L german -C din5007-utf8 ',
+    'is': '-L icelandic -C utf8 ',
+    'it': '-L italian -C utf8 ',
+    'la': '-L latin -C utf8 ',
+    'lv': '-L latvian -C utf8 ',
+    'lt': '-L lithuanian -C utf8 ',
+    'dsb': '-L lower-sorbian -C utf8 ',
+    'ds': '-L lower-sorbian -C utf8 ',   # trick, no conflict
+    'nb': '-L norwegian -C utf8 ',
+    'no': '-L norwegian -C utf8 ',       # and what about nynorsk?
+    'pl': '-L polish -C utf8 ',
+    'pt': '-L portuguese -C utf8 ',
+    'ro': '-L romanian -C utf8 ',
+    'sk': '-L slovak -C small-utf8 ',    # there is also slovak-large
+    'sl': '-L slovenian -C utf8 ',
+    'es': '-L spanish -C modern-utf8 ',  # there is also spanish-traditional
+    'sv': '-L swedish -C utf8 ',
+    'tr': '-L turkish -C utf8 ',
+    'hsb': '-L upper-sorbian -C utf8 ',
+    'hs': '-L upper-sorbian -C utf8 ',   # trick, no conflict
+    'vi': '-L vietnamese -C utf8 ',
+    # CYRILLIC
+    # for usage with pdflatex, needs also cyrLICRutf8.xdy module
+    'be': '-L belarusian -C utf8 ',
+    'bg': '-L bulgarian -C utf8 ',
+    'mk': '-L macedonian -C utf8 ',
+    'mn': '-L mongolian -C cyrillic-utf8 ',
+    'ru': '-L russian -C utf8 ',
+    'sr': '-L serbian -C utf8 ',
+    'sh-cyrl': '-L serbian -C utf8 ',
+    'sh': '-L serbian -C utf8 ',         # trick, no conflict
+    'uk': '-L ukrainian -C utf8 ',
+    # GREEK
+    # can work only with xelatex/lualatex, not supported by texindy+pdflatex
+    'el': '-L greek -C utf8 ',
+    # FIXME, not compatible with [:2] slice but does Sphinx support Greek ?
+    'el-polyton': '-L greek -C polytonic-utf8 ',
+}  # type: Dict[unicode, unicode]
+
+XINDY_CYRILLIC_SCRIPTS = [
+    'be', 'bg', 'mk', 'mn', 'ru', 'sr', 'sh', 'uk',
+]  # type: List[unicode]
+
 logger = logging.getLogger(__name__)
 
 
@@ -232,7 +293,23 @@ def finish(self):
         self.copy_image_files()
 
         # copy TeX support files from texinputs
-        context = {'latex_engine': self.config.latex_engine}
+        # configure usage of xindy (impacts Makefile and latexmkrc)
+        # FIXME: convert this rather to a confval with suitable default
+        #        according to language ? but would require extra documentation
+        if self.config.language:
+            xindy_lang_option = \
+                XINDY_LANG_OPTIONS.get(self.config.language[:2],
+                                       '-L general -C utf8 ')
+            xindy_cyrillic = self.config.language[:2] in XINDY_CYRILLIC_SCRIPTS
+        else:
+            xindy_lang_option = '-L english -C utf8 '
+            xindy_cyrillic = False
+        context = {
+            'latex_engine':      self.config.latex_engine,
+            'xindy_use':         self.config.latex_use_xindy,
+            'xindy_lang_option': xindy_lang_option,
+            'xindy_cyrillic':    xindy_cyrillic,
+        }
         logger.info(bold(__('copying TeX support files...')))
         staticdirname = path.join(package_dir, 'texinputs')
         for filename in os.listdir(staticdirname):
@@ -317,6 +394,12 @@ def default_latex_docclass(config):
         return {}
 
 
+def default_latex_use_xindy(config):
+    # type: (Config) -> bool
+    """ Better default latex_use_xindy settings for specific engines. """
+    return config.latex_engine in {'xelatex', 'lualatex'}
+
+
 def setup(app):
     # type: (Sphinx) -> Dict[unicode, Any]
     app.add_builder(LaTeXBuilder)
@@ -334,6 +417,7 @@ def setup(app):
     app.add_config_value('latex_logo', None, None, string_classes)
     app.add_config_value('latex_appendices', [], None)
     app.add_config_value('latex_use_latex_multicolumn', False, None)
+    app.add_config_value('latex_use_xindy', default_latex_use_xindy, None)
     app.add_config_value('latex_toplevel_sectioning', None, None,
                          ENUM(None, 'part', 'chapter', 'section'))
     app.add_config_value('latex_domain_indices', True, None, [list])
diff --git a/sphinx/templates/latex/latex.tex_t b/sphinx/templates/latex/latex.tex_t
index 0ea75557f..d219f8525 100644
--- a/sphinx/templates/latex/latex.tex_t
+++ b/sphinx/templates/latex/latex.tex_t
@@ -13,6 +13,11 @@
 \ifdefined\pdfpxdimen
    \let\sphinxpxdimen\pdfpxdimen\else\newdimen\sphinxpxdimen
 \fi \sphinxpxdimen=<%= pxunit %>\relax
+<% if use_xindy -%>
+%% turn off hyperref patch of \index as sphinx.xdy xindy module takes care of
+%% suitable \hyperpage mark-up, working around hyperref-xindy incompatibility
+\PassOptionsToPackage{hyperindex=false}{hyperref}
+<% endif -%>
 <%= passoptionstopackages %>
 \PassOptionsToPackage{warn}{textcomp}
 <%= inputenc %>
@@ -31,7 +36,7 @@
 <%= hyperref %>
 <%= contentsname %>
 <%= numfig_format %>
-<%= literalblockpto %>
+<%= translatablestrings %>
 <%= pageautorefname %>
 <%= tocdepth %>
 <%= secnumdepth %>
diff --git a/sphinx/texinputs/Makefile_t b/sphinx/texinputs/Makefile_t
index 06bd6c4d7..1ce4b1324 100644
--- a/sphinx/texinputs/Makefile_t
+++ b/sphinx/texinputs/Makefile_t
@@ -22,6 +22,15 @@ export LATEXOPTS =
 # or on command line for faster builds.
 {% endif -%}
 LATEXMKOPTS =
+{% if xindy_use -%}
+export XINDYOPTS = {{ xindy_lang_option }} -M sphinx.xdy
+{% if latex_engine == 'pdflatex' and xindy_cyrillic -%}
+XINDYOPTS += -M cyrLICRutf8.xdy
+{% endif -%}
+{% if latex_engine == 'xelatex' or latex_engine == 'lualatex' -%}
+XINDYOPTS += -I xelatex
+{% endif -%}
+{% endif -%}
 # format: pdf or dvi (used only by archive targets)
 FMT = pdf
 
diff --git a/sphinx/texinputs/cyrLICRutf8.xdy b/sphinx/texinputs/cyrLICRutf8.xdy
new file mode 100644
index 000000000..86d8cd87b
--- /dev/null
+++ b/sphinx/texinputs/cyrLICRutf8.xdy
@@ -0,0 +1,103 @@
+;; -*- coding: utf-8; mode: Lisp; -*-
+;; style file for xindy
+;; filename: cyrLICRutf8.xdy
+;; description: style file for xindy which maps back LaTeX Internal
+;;   Character Representation of Cyrillic to utf-8
+;; usage: for use with pdflatex produced .idx files.
+;; This module must be loaded after the rule for suppressing space
+;; characters has been executed, hence after module sphinx.xdy.
+;; Contributed by the Sphinx team, July 2018.
+(merge-rule "\IeC{\'\CYRG}" "Ѓ" :string)
+(merge-rule "\IeC{\'\CYRK}" "Ќ" :string)
+(merge-rule "\IeC{\'\cyrg}" "ѓ" :string)
+(merge-rule "\IeC{\'\cyrk}" "ќ" :string)
+(merge-rule "\IeC{\CYRA}" "А" :string)
+(merge-rule "\IeC{\CYRB}" "Б" :string)
+(merge-rule "\IeC{\CYRC}" "Ц" :string)
+(merge-rule "\IeC{\CYRCH}" "Ч" :string)
+(merge-rule "\IeC{\CYRD}" "Д" :string)
+(merge-rule "\IeC{\CYRDJE}" "Ђ" :string)
+(merge-rule "\IeC{\CYRDZE}" "Ѕ" :string)
+(merge-rule "\IeC{\CYRDZHE}" "Џ" :string)
+(merge-rule "\IeC{\CYRE}" "Е" :string)
+(merge-rule "\IeC{\CYREREV}" "Э" :string)
+(merge-rule "\IeC{\CYRERY}" "Ы" :string)
+(merge-rule "\IeC{\CYRF}" "Ф" :string)
+(merge-rule "\IeC{\CYRG}" "Г" :string)
+(merge-rule "\IeC{\CYRGUP}" "Ґ" :string)
+(merge-rule "\IeC{\CYRH}" "Х" :string)
+(merge-rule "\IeC{\CYRHRDSN}" "Ъ" :string)
+(merge-rule "\IeC{\CYRI}" "И" :string)
+(merge-rule "\IeC{\CYRIE}" "Є" :string)
+(merge-rule "\IeC{\CYRII}" "І" :string)
+(merge-rule "\IeC{\CYRISHRT}" "Й" :string)
+(merge-rule "\IeC{\CYRJE}" "Ј" :string)
+(merge-rule "\IeC{\CYRK}" "К" :string)
+(merge-rule "\IeC{\CYRL}" "Л" :string)
+(merge-rule "\IeC{\CYRLJE}" "Љ" :string)
+(merge-rule "\IeC{\CYRM}" "М" :string)
+(merge-rule "\IeC{\CYRN}" "Н" :string)
+(merge-rule "\IeC{\CYRNJE}" "Њ" :string)
+(merge-rule "\IeC{\CYRO}" "О" :string)
+(merge-rule "\IeC{\CYRP}" "П" :string)
+(merge-rule "\IeC{\CYRR}" "Р" :string)
+(merge-rule "\IeC{\CYRS}" "С" :string)
+(merge-rule "\IeC{\CYRSFTSN}" "Ь" :string)
+(merge-rule "\IeC{\CYRSH}" "Ш" :string)
+(merge-rule "\IeC{\CYRSHCH}" "Щ" :string)
+(merge-rule "\IeC{\CYRT}" "Т" :string)
+(merge-rule "\IeC{\CYRTSHE}" "Ћ" :string)
+(merge-rule "\IeC{\CYRU}" "У" :string)
+(merge-rule "\IeC{\CYRUSHRT}" "Ў" :string)
+(merge-rule "\IeC{\CYRV}" "В" :string)
+(merge-rule "\IeC{\CYRYA}" "Я" :string)
+(merge-rule "\IeC{\CYRYI}" "Ї" :string)
+(merge-rule "\IeC{\CYRYO}" "Ё" :string)
+(merge-rule "\IeC{\CYRYU}" "Ю" :string)
+(merge-rule "\IeC{\CYRZ}" "З" :string)
+(merge-rule "\IeC{\CYRZH}" "Ж" :string)
+(merge-rule "\IeC{\cyra}" "а" :string)
+(merge-rule "\IeC{\cyrb}" "б" :string)
+(merge-rule "\IeC{\cyrc}" "ц" :string)
+(merge-rule "\IeC{\cyrch}" "ч" :string)
+(merge-rule "\IeC{\cyrd}" "д" :string)
+(merge-rule "\IeC{\cyrdje}" "ђ" :string)
+(merge-rule "\IeC{\cyrdze}" "ѕ" :string)
+(merge-rule "\IeC{\cyrdzhe}" "џ" :string)
+(merge-rule "\IeC{\cyre}" "е" :string)
+(merge-rule "\IeC{\cyrerev}" "э" :string)
+(merge-rule "\IeC{\cyrery}" "ы" :string)
+(merge-rule "\IeC{\cyrf}" "ф" :string)
+(merge-rule "\IeC{\cyrg}" "г" :string)
+(merge-rule "\IeC{\cyrgup}" "ґ" :string)
+(merge-rule "\IeC{\cyrh}" "х" :string)
+(merge-rule "\IeC{\cyrhrdsn}" "ъ" :string)
+(merge-rule "\IeC{\cyri}" "и" :string)
+(merge-rule "\IeC{\cyrie}" "є" :string)
+(merge-rule "\IeC{\cyrii}" "і" :string)
+(merge-rule "\IeC{\cyrishrt}" "й" :string)
+(merge-rule "\IeC{\cyrje}" "ј" :string)
+(merge-rule "\IeC{\cyrk}" "к" :string)
+(merge-rule "\IeC{\cyrl}" "л" :string)
+(merge-rule "\IeC{\cyrlje}" "љ" :string)
+(merge-rule "\IeC{\cyrm}" "м" :string)
+(merge-rule "\IeC{\cyrn}" "н" :string)
+(merge-rule "\IeC{\cyrnje}" "њ" :string)
+(merge-rule "\IeC{\cyro}" "о" :string)
+(merge-rule "\IeC{\cyrp}" "п" :string)
+(merge-rule "\IeC{\cyrr}" "р" :string)
+(merge-rule "\IeC{\cyrs}" "с" :string)
+(merge-rule "\IeC{\cyrsftsn}" "ь" :string)
+(merge-rule "\IeC{\cyrsh}" "ш" :string)
+(merge-rule "\IeC{\cyrshch}" "щ" :string)
+(merge-rule "\IeC{\cyrt}" "т" :string)
+(merge-rule "\IeC{\cyrtshe}" "ћ" :string)
+(merge-rule "\IeC{\cyru}" "у" :string)
+(merge-rule "\IeC{\cyrushrt}" "ў" :string)
+(merge-rule "\IeC{\cyrv}" "в" :string)
+(merge-rule "\IeC{\cyrya}" "я" :string)
+(merge-rule "\IeC{\cyryi}" "ї" :string)
+(merge-rule "\IeC{\cyryo}" "ё" :string)
+(merge-rule "\IeC{\cyryu}" "ю" :string)
+(merge-rule "\IeC{\cyrz}" "з" :string)
+(merge-rule "\IeC{\cyrzh}" "ж" :string)
diff --git a/sphinx/texinputs/latexmkrc_t b/sphinx/texinputs/latexmkrc_t
index e3cd14f48..d52681fbd 100644
--- a/sphinx/texinputs/latexmkrc_t
+++ b/sphinx/texinputs/latexmkrc_t
@@ -10,7 +10,11 @@ $pdflatex = 'xelatex ' . $ENV{'LATEXOPTS'} . ' %O %S';
 {% endif -%}
 $lualatex = 'lualatex ' . $ENV{'LATEXOPTS'} . ' %O %S';
 $xelatex = 'xelatex --no-pdf ' . $ENV{'LATEXOPTS'} . ' %O %S';
+{% if xindy_use -%}
+$makeindex = 'xindy ' . $ENV{'XINDYOPTS'} . ' %O -o %D %S';
+{% else -%}
 $makeindex = 'makeindex -s python.ist %O -o %D %S';
+{% endif -%}
 add_cus_dep( "glo", "gls", 0, "makeglo" );
 sub makeglo {
  return system( "makeindex -s gglo.ist -o '$_[0].gls' '$_[0].glo'" );
diff --git a/sphinx/texinputs/sphinx.sty b/sphinx/texinputs/sphinx.sty
index 3333fcc62..30d8891e0 100644
--- a/sphinx/texinputs/sphinx.sty
+++ b/sphinx/texinputs/sphinx.sty
@@ -6,7 +6,7 @@
 %
 
 \NeedsTeXFormat{LaTeX2e}[1995/12/01]
-\ProvidesPackage{sphinx}[2018/03/28 v1.8 LaTeX package (Sphinx markup)]
+\ProvidesPackage{sphinx}[2018/06/30 v1.8 LaTeX package (Sphinx markup)]
 
 % provides \ltx@ifundefined
 % (many packages load ltxcmds: graphicx does for pdftex and lualatex but
@@ -470,6 +470,8 @@
  {\newenvironment{sphinxtheindex}{\begin{theindex}}{\end{theindex}}}%
  {}% else clause of \ltx@ifundefined
 
+% for usage with xindy: this string gets internationalized in preamble
+\newcommand*{\sphinxnonalphabeticalgroupname}{}
 % redefined in preamble, headings for makeindex produced index
 \newcommand*{\sphinxsymbolsname}{}
 \newcommand*{\sphinxnumbersname}{}
@@ -1594,11 +1596,13 @@
   {\textnormal{\Large[}}{#1}\hspace{0.5mm}{\textnormal{\Large]}}}
 
 % additional customizable styling
-% FIXME: convert this to package options ?
 \def\sphinxstyleindexentry   #1{\texttt{#1}}
 \def\sphinxstyleindexextra   #1{ \emph{(#1)}}
 \def\sphinxstyleindexpageref #1{, \pageref{#1}}
-\def\sphinxstyleindexlettergroup #1{{\Large\sffamily#1}\nopagebreak\vspace{1mm}}
+\def\sphinxstyleindexlettergroup #1%
+    {{\Large\sffamily#1}\nopagebreak\vspace{1mm}}
+\def\sphinxstyleindexlettergroupDefault #1%
+    {{\Large\sffamily\sphinxnonalphabeticalgroupname}\nopagebreak\vspace{1mm}}
 \protected\def\sphinxstyletopictitle   #1{\textbf{#1}\par\medskip}
 \let\sphinxstylesidebartitle\sphinxstyletopictitle
 \protected\def\sphinxstyleothertitle   #1{\textbf{#1}}
diff --git a/sphinx/texinputs/sphinx.xdy b/sphinx/texinputs/sphinx.xdy
new file mode 100644
index 000000000..d9f99dc2a
--- /dev/null
+++ b/sphinx/texinputs/sphinx.xdy
@@ -0,0 +1,133 @@
+;;; -*- mode: lisp; coding: utf-8; -*-
+
+;; Unfortunately xindy is out-of-the-box hyperref-incompatible.  This
+;; configuration is a workaround, which requires to pass option
+;; hyperindex=false to hyperref.
+;; textit and emph not currently used by Sphinx LaTeX writer.
+(define-attributes (("textbf" "textit" "emph" "default")))
+(markup-locref :open "\textbf{\hyperpage{" :close "}}" :attr "textbf")
+(markup-locref :open "\textit{\hyperpage{" :close "}}" :attr "textit")
+(markup-locref :open "\emph{\hyperpage{" :close "}}" :attr "emph")
+(markup-locref :open "\hyperpage{" :close "}" :attr "default")
+
+(require "numeric-sort.xdy")
+
+;; xindy base module latex.xdy loads tex.xdy and the latter instructs
+;; xindy to ignore **all** TeX macros in .idx entries, except those
+;; explicitely described in merge rule.  But when after applying all
+;; merge rules an empty string results, xindy raises an error:
+
+;;   ERROR: CHAR: index 0 should be less than the length of the string
+
+;; For example when using pdflatex with utf-8 characters the index
+;; file will contain \IeC macros and they will get ignored except if
+;; suitable merge rules are loaded early.  The texindy script coming
+;; with xindy provides this, but only for Latin scripts.  The texindy
+;; man page says to use rather xelatex or lualatex in case of Cyrillic
+;; scripts.
+
+;; Sphinx contributes cyrLICRutf8.xdy to provide support for Cyrillic
+;; scripts for the pdflatex engine.
+
+;; Another issue caused by xindy ignoring all TeX macros except those
+;; explicitely declared reveals itself when attempting to index ">>>",
+;; as the ">" is converted to "\textgreater{}" by Sphinx's LaTeX
+;; escaping.
+
+;; To fix this, Sphinx does **not** use texindy, and does not even
+;; load the xindy latex.xdy base module.
+
+;(require "latex.xdy")
+
+;; Rather it incorporates some suitable extracts from latex.xdy and
+;; tex.xdy with additional Sphinx contributed rules.
+
+;;;;;;;; extracts from tex.xdy (discarding most original comments):
+
+;;;
+;;; TeX conventions
+;;;
+
+;; Discard leading and trailing white space. Collapse multiple white
+;; space characters to blank.
+
+(merge-rule "^ +" "" :eregexp)
+(merge-rule " +$" "" :eregexp)
+(merge-rule "  +" " " :eregexp)
+
+;; Handle TeX markup
+
+(merge-rule "\\([{}$%&#])" "\1" :eregexp)
+
+;;;;;;;; end of extracts from xindy's tex.xdy
+
+;;;;;;;; extracts from latex.xdy:
+
+;; Standard location classes: arabic and roman numbers, and alphabets.
+
+(define-location-class "arabic-page-numbers" ("arabic-numbers"))
+(define-location-class "roman-page-numbers"  ("roman-numbers-lowercase"))
+(define-location-class "Roman-page-numbers"  ("roman-numbers-uppercase"))
+(define-location-class "alpha-page-numbers"  ("alpha"))
+(define-location-class "Alpha-page-numbers"  ("ALPHA"))
+
+;; Output Markup
+
+(markup-letter-group-list :sep "~n~n  \indexspace~n")
+
+(markup-indexentry :open "~n  \item "           :depth 0)
+(markup-indexentry :open "~n    \subitem "      :depth 1)
+(markup-indexentry :open "~n      \subsubitem " :depth 2)
+
+(markup-locclass-list :open ", " :sep ", ")
+(markup-locref-list   :sep ", ")
+
+;;;;;;;; end of extracts from latex.xdy
+
+;; Sphinx additions, cf sphinx.util.texescape for rationale
+;;
+;; blanks are already ignored from above merge-rules, so no space
+;; character after TeX control words, despite the fact that they will
+;; be present in .idx file.
+
+(merge-rule "\\sphinxleftcurlybrace\{\}" "{")
+(merge-rule "\\sphinxrightcurlybrace\{\}" "}")
+(merge-rule "\\_" "_")
+(merge-rule "\{\[\}" "[")
+(merge-rule "\{\]\}" "]")
+(merge-rule "\{\}`" "`")
+(merge-rule "\\textbackslash\{\}" "\\")
+(merge-rule "\\textasciitilde\{\}" "~~")
+(merge-rule "\\textless\{\}" "<")
+(merge-rule "\\textgreater\{\}" ">")
+(merge-rule "\\textasciicircum\{\}" "^")
+(merge-rule "\\P\{\}" "¶")
+(merge-rule "\\S\{\}" "§")
+(merge-rule "\\texteuro\{\}" "€")
+(merge-rule "\\\(\\infty\\\)" "∞")
+(merge-rule "\\\(\\pm\\\)" "±")
+(merge-rule "\\\(\\rightarrow\\\)" "→")
+(merge-rule "\\\(\\checkmark\\\)" "✓")
+(merge-rule "\\textendash\{\}" "–")
+(merge-rule "\\textbar\{\}" "|")
+
+;; This xindy module provides some basic support for "see"
+(require "makeindex.xdy")
+
+;; This creates one-letter headings and works fine with utf-8 letters.
+;; For Cyrillic and pdflatex necessitates cyrLICRutf8.xdy to be loaded too.
+(require "latin-lettergroups.xdy")
+
+;; currently we don't (know how to easily) separate "Numbers" from
+;; "Symbols" with xindy as is the case with makeindex.
+(markup-index :open  "\begin{sphinxtheindex}
+\let\lettergroup\sphinxstyleindexlettergroup
+\let\lettergroupDefault\sphinxstyleindexlettergroupDefault
+
+"
+	      :close "
+
+\end{sphinxtheindex}
+"
+	      :tree)
+
diff --git a/sphinx/writers/latex.py b/sphinx/writers/latex.py
index 3b5a4f3e8..97fa300e1 100644
--- a/sphinx/writers/latex.py
+++ b/sphinx/writers/latex.py
@@ -130,7 +130,7 @@
     'tocdepth':        '',
     'secnumdepth':     '',
     'pageautorefname': '',
-    'literalblockpto': '',
+    'translatablestrings': '',
 }  # type: Dict[unicode, unicode]
 
 ADDITIONAL_SETTINGS = {
@@ -497,6 +497,7 @@ def __init__(self, document, builder):
             'release':      self.encode(builder.config.release),
             'author':       document.settings.author,   # treat as a raw LaTeX code
             'indexname':    _('Index'),
+            'use_xindy':    builder.config.latex_use_xindy,
         })
         if not self.elements['releasename'] and self.elements['release']:
             self.elements.update({
@@ -667,13 +668,16 @@ def declare_package(packagename, options=None):
         if self.elements['extraclassoptions']:
             self.elements['classoptions'] += ',' + \
                                              self.elements['extraclassoptions']
-        self.elements['literalblockpto'] = (
+        self.elements['translatablestrings'] = (
             self.babel_renewcommand(
                 '\\literalblockcontinuedname', self.encode(_('continued from previous page'))
             ) +
             self.babel_renewcommand(
                 '\\literalblockcontinuesname', self.encode(_('continues on next page'))
             ) +
+            self.babel_renewcommand(
+                '\\sphinxnonalphabeticalgroupname', self.encode(_('Non-alphabetical'))
+            ) +
             self.babel_renewcommand(
                 '\\sphinxsymbolsname', self.encode(_('Symbols'))
             ) +
@@ -871,7 +875,8 @@ def generate(content, collapsed):
                 for entry in entries:
                     if not entry[3]:
                         continue
-                    ret.append('\\item {\\sphinxstyleindexentry{%s}}' % self.encode(entry[0]))
+                    ret.append('\\item\\relax\\sphinxstyleindexentry{%s}' %
+                               self.encode(entry[0]))
                     if entry[4]:
                         # add "extra" info
                         ret.append('\\sphinxstyleindexextra{%s}' % self.encode(entry[4]))
@@ -1924,8 +1929,11 @@ def visit_index(self, node, scre=re.compile(r';\s*')):
         # type: (nodes.Node, Pattern) -> None
         def escape(value):
             value = self.encode(value)
-            value = value.replace(r'\{', r'{\sphinxleftcurlybrace}')
-            value = value.replace(r'\}', r'{\sphinxrightcurlybrace}')
+            value = value.replace(r'\{', r'\sphinxleftcurlybrace{}')
+            value = value.replace(r'\}', r'\sphinxrightcurlybrace{}')
+            value = value.replace('"', '""')
+            value = value.replace('@', '"@')
+            value = value.replace('!', '"!')
             return value
 
         if not node.get('inline', True):


Test patch:
diff --git a/tests/test_build_latex.py b/tests/test_build_latex.py
index 2573a74da..8075bf8d0 100644
--- a/tests/test_build_latex.py
+++ b/tests/test_build_latex.py
@@ -1201,7 +1201,7 @@ def test_latex_index(app, status, warning):
     result = (app.outdir / 'Python.tex').text(encoding='utf8')
     assert 'A \\index{famous}famous \\index{equation}equation:\n' in result
     assert '\n\\index{Einstein}\\index{relativity}\\ignorespaces \nand' in result
-    assert '\n\\index{main {\\sphinxleftcurlybrace}}\\ignorespaces ' in result
+    assert '\n\\index{main \\sphinxleftcurlybrace{}}\\ignorespaces ' in result
 
 
 @pytest.mark.sphinx('latex', testroot='latex-equations')