# Prerequisites

ISO C++ Prerequisites

Because libstdc++ is part of GCC, the primary source for installation instructions is the GCC install page. In particular, list of prerequisite software needed to build the library starts with those requirements. The same pages also list the tools you will need if you wish to modify the source.

Additional data is given here only where it applies to libstdc++.

As of GCC 4.0.1 the minimum version of binutils required to build libstdc++ is `2.15.90.0.1.1`. Older releases of libstdc++ do not require such a recent version, but to take full advantage of useful space-saving features and bug-fixes you should use a recent binutils whenever possible. The configure process will automatically detect and use these features if the underlying support is present.

To generate the API documentation from the sources you will need Doxygen, see Documentation Hacking in the appendix for full details.

Finally, a few system-specific requirements:

linux

  If GCC 3.1.0 or later on is being used on GNU/Linux, an attempt will be made to use "C" library functionality necessary for C++ named locale support. For GCC 4.6.0 and later, this means that glibc 2.3 or later is required.

  If the 'gnu' locale model is being used, the following locales are used and tested in the libstdc++ testsuites. The first column is the name of the locale, the second is the character set it is expected to use.

      de_DE               ISO-8859-1
      de_DE@euro          ISO-8859-15
      en_GB               ISO-8859-1
      en_HK               ISO-8859-1
      en_PH               ISO-8859-1
      en_US               ISO-8859-1
      en_US.ISO-8859-1    ISO-8859-1
      en_US.ISO-8859-15   ISO-8859-15
      en_US.UTF-8         UTF-8
      es_ES               ISO-8859-1
      es_MX               ISO-8859-1
      fr_FR               ISO-8859-1
      fr_FR@euro          ISO-8859-15
      is_IS               UTF-8
      it_IT               ISO-8859-1
      ja_JP.eucjp         EUC-JP
      ru_RU.ISO-8859-5    ISO-8859-5
      ru_RU.UTF-8         UTF-8
      se_NO.UTF-8         UTF-8
      ta_IN               UTF-8
      zh_TW               BIG5

  Failure to have installed the underlying "C" library locale information for any of the above regions means that the corresponding C++ named locale will not work: because of this, the libstdc++ testsuite will skip named locale tests which need missing information. If this isn't an issue, don't worry about it. If a named locale is needed, the underlying locale information must be installed. Note that rebuilding libstdc++ after "C" locales are installed is not necessary.

  To install support for locales, do only one of the following:

  - install all locales

  - install just the necessary locales

    - with Debian GNU/Linux:

      Add the above list, as shown, to the file `/etc/locale.gen`

      run `/usr/sbin/locale-gen`

    - on most Unix-like operating systems:

      `localedef -i de_DE -f ISO-8859-1 de_DE`

      (repeat for each entry in the above list)

    - Instructions for other operating systems solicited.