lix/doc/manual/installation
Niklas Hambüchen 57daa860e8 autoconf: Fix C++17 detection not working on Ubuntu 16.04.
And probably many other distributions.

Until now, ./configure would fail silently printing a warning

    ./configure: line 4621: AX_CXX_COMPILE_STDCXX_17: command not found

and then continuing, later failing with a C++ #error saying that some C++11
feature isn't supported (it didn't even get to the C++17 features).

This is because older distributions don't come with the
`AX_CXX_COMPILE_STDCXX_17` m4 macro.

This commit vendors that macro accordingly.

Now ./configure complains correctly:

    configure: error: *** A compiler with support for C++17 language features is required.

On Ubuntu 16.04, ./configure completes if a newer compiler is used, e.g. with
gcc-7 from https://launchpad.net/~ubuntu-toolchain-r/+archive/ubuntu/test
using:

    ./bootstrap.sh
    ./configure CXX=g++-7 --disable-doc-gen --with-boost=$(nix-build --no-link '<nixpkgs>' -A boost.dev)
2019-07-03 04:32:25 +02:00
..
building-source.xml Rely on XML catalogs to find the DocBook schemas and stylesheets 2014-11-25 15:54:26 +01:00
env-variables.xml Document the multi-user installer some 2018-09-01 10:45:50 -04:00
installation.xml Restructuring the Nix manual 2014-08-27 18:41:09 +02:00
installing-binary.xml Document the multi-user installer some 2018-09-01 10:45:50 -04:00
installing-source.xml Manual build fixes 2014-09-16 14:14:09 +02:00
multi-user.xml Remove macOS multi-user instructions 2018-02-19 20:40:25 +01:00
nix-security.xml Restructuring the Nix manual 2014-08-27 18:41:09 +02:00
obtaining-source.xml Restructuring the Nix manual 2014-08-27 18:41:09 +02:00
prerequisites-source.xml autoconf: Fix C++17 detection not working on Ubuntu 16.04. 2019-07-03 04:32:25 +02:00
single-user.xml Restructuring the Nix manual 2014-08-27 18:41:09 +02:00
supported-platforms.xml We support aarch64 now 2018-09-01 10:44:33 -04:00
upgrading.xml Upgrade docs: improve the upgrade command 2018-09-19 14:17:06 -04:00