Some notes on how to build Litecoin Core in Unix.

(for OpenBSD specific instructions, see build-openbsd.md)

Always use absolute paths to configure and compile litecoin and the dependencies, for example, when specifying the path of the dependency:

../dist/configure --enable-cxx --disable-shared --with-pic --prefix=$BDB_PREFIX

Here BDB_PREFIX must be an absolute path - it is defined using $(pwd) which ensures the usage of the absolute path.

./autogen.sh
./configure
make
make install # optional

This will build litecoin-qt as well if the dependencies are met.

These dependencies are required:

Optional dependencies:

For the versions used, see dependencies.md

C++ compilers are memory-hungry. It is recommended to have at least 1.5 GB of memory available when compiling Litecoin Core. On systems with less, gcc can be tuned to conserve memory with additional CXXFLAGS:

./configure CXXFLAGS="--param ggc-min-expand=1 --param ggc-min-heapsize=32768"

Build requirements:

sudo apt-get install build-essential libtool autotools-dev automake pkg-config libssl-dev libevent-dev bsdmainutils python3

Options when installing required Boost library files:

1. On at least Ubuntu 14.04+ and Debian 7+ there are generic names for the individual boost development packages, so the following can be used to only install necessary parts of boost:

    sudo apt-get install libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-program-options-dev libboost-test-dev libboost-thread-dev
   

2. If that doesn't work, you can install all boost development packages with:

    sudo apt-get install libboost-all-dev
   

BerkeleyDB is required for the wallet.

For Ubuntu only: db4.8 packages are available here. You can add the repository and install using the following commands:

sudo apt-get install software-properties-common
sudo add-apt-repository ppa:bitcoin/bitcoin
sudo apt-get update
sudo apt-get install libdb4.8-dev libdb4.8++-dev

Ubuntu and Debian have their own libdb-dev and libdb++-dev packages, but these will install BerkeleyDB 5.1 or later, which break binary wallet compatibility with the distributed executables which are based on BerkeleyDB 4.8. If you do not care about wallet compatibility, pass --with-incompatible-bdb to configure.

See the section "Disable-wallet mode" to build Litecoin Core without wallet.

Optional (see --with-miniupnpc and --enable-upnp-default):

sudo apt-get install libminiupnpc-dev

ZMQ dependencies (provides ZMQ API 4.x):

sudo apt-get install libzmq3-dev

If you want to build Litecoin-Qt, make sure that the required packages for Qt development are installed. Either Qt 5 or Qt 4 are necessary to build the GUI. If both Qt 4 and Qt 5 are installed, Qt 5 will be used. Pass --with-gui=qt4 to configure to choose Qt4. To build without GUI pass --without-gui.

To build with Qt 5 (recommended) you need the following:

sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 qttools5-dev qttools5-dev-tools libprotobuf-dev protobuf-compiler

Alternatively, to build with Qt 4 you need the following:

sudo apt-get install libqt4-dev libprotobuf-dev protobuf-compiler

libqrencode (optional) can be installed with:

sudo apt-get install libqrencode-dev

Once these are installed, they will be found by configure and a litecoin-qt executable will be built by default.

Build requirements:

sudo dnf install gcc-c++ libtool make autoconf automake openssl-devel libevent-devel boost-devel libdb4-devel libdb4-cxx-devel python3

Optional:

sudo dnf install miniupnpc-devel

To build with Qt 5 (recommended) you need the following:

sudo dnf install qt5-qttools-devel qt5-qtbase-devel protobuf-devel

libqrencode (optional) can be installed with:

sudo dnf install qrencode-devel

The release is built with GCC and then "strip litecoind" to strip the debug symbols, which reduces the executable size by about 90%.

miniupnpc may be used for UPnP port mapping. It can be downloaded from here. UPnP support is compiled in and turned off by default. See the configure options for upnp behavior desired:

--without-miniupnpc      No UPnP support miniupnp not required
--disable-upnp-default   (the default) UPnP support turned off by default at runtime
--enable-upnp-default    UPnP support turned on by default at runtime

It is recommended to use Berkeley DB 4.8. If you have to build it yourself, you can use the installation script included in contrib/ like so

./contrib/install_db4.sh `pwd`

from the root of the repository.

Note: You only need Berkeley DB if the wallet is enabled (see the section Disable-Wallet mode below).

If you need to build Boost yourself:

sudo su
./bootstrap.sh
./bjam install

To help make your litecoin installation more secure by making certain attacks impossible to exploit even if a vulnerability is found, binaries are hardened by default. This can be disabled with:

Hardening Flags:

./configure --enable-hardening
./configure --disable-hardening

Hardening enables the following features:

• Position Independent Executable Build position independent code to take advantage of Address Space Layout Randomization offered by some kernels. Attackers who can cause execution of code at an arbitrary memory location are thwarted if they don't know where anything useful is located. The stack and heap are randomly located by default but this allows the code section to be randomly located as well.

  On an AMD64 processor where a library was not compiled with -fPIC, this will cause an error such as: "relocation R_X86_64_32 against `......' can not be used when making a shared object;"

  To test that you have built PIE executable, install scanelf, part of paxutils, and use:

    scanelf -e ./litecoin
  

  The output should contain:

  TYPE ET_DYN

• Non-executable Stack If the stack is executable then trivial stack based buffer overflow exploits are possible if vulnerable buffers are found. By default, litecoin should be built with a non-executable stack but if one of the libraries it uses asks for an executable stack or someone makes a mistake and uses a compiler extension which requires an executable stack, it will silently build an executable without the non-executable stack protection.

  To verify that the stack is non-executable after compiling use: scanelf -e ./litecoin

  the output should contain: STK/REL/PTL RW- R-- RW-

  The STK RW- means that the stack is readable and writeable but not executable.

When the intention is to run only a P2P node without a wallet, litecoin may be compiled in disable-wallet mode with:

./configure --disable-wallet

In this case there is no dependency on Berkeley DB 4.8.

Mining is also possible in disable-wallet mode, but only using the getblocktemplate RPC call not getwork.

A list of additional configure flags can be displayed with:

./configure --help

This example lists the steps necessary to setup and build a command line only, non-wallet distribution of the latest changes on Arch Linux:

pacman -S git base-devel boost libevent python
git clone https://github.com/litecoin-project/litecoin.git
cd litecoin/
./autogen.sh
./configure --disable-wallet --without-gui --without-miniupnpc
make check

Note: Enabling wallet support requires either compiling against a Berkeley DB newer than 4.8 (package db) using --with-incompatible-bdb, or building and depending on a local version of Berkeley DB 4.8. The readily available Arch Linux packages are currently built using --with-incompatible-bdb according to the PKGBUILD. As mentioned above, when maintaining portability of the wallet between the standard Litecoin Core distributions and independently built node software is desired, Berkeley DB 4.8 must be used.

These steps can be performed on, for example, an Ubuntu VM. The depends system will also work on other Linux distributions, however the commands for installing the toolchain will be different.

Make sure you install the build requirements mentioned above. Then, install the toolchain and curl:

sudo apt-get install g++-arm-linux-gnueabihf curl

To build executables for ARM:

cd depends
make HOST=arm-linux-gnueabihf NO_QT=1
cd ..
./configure --prefix=$PWD/depends/arm-linux-gnueabihf --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++
make

For further documentation on the depends system see README.md in the depends directory.

(Updated as of FreeBSD 11.0)

Clang is installed by default as cc compiler, this makes it easier to get started than on OpenBSD. Installing dependencies:

pkg install autoconf automake libtool pkgconf
pkg install boost-libs openssl libevent
pkg install gmake

You need to use GNU make (gmake) instead of make. (libressl instead of openssl will also work)

For the wallet (optional):

./contrib/install_db4.sh `pwd`
setenv BDB_PREFIX $PWD/db4

Then build using:

./autogen.sh
./configure BDB_CFLAGS="-I${BDB_PREFIX}/include" BDB_LIBS="-L${BDB_PREFIX}/lib -ldb_cxx"
gmake

Note on debugging: The version of gdb installed by default is ancient and considered harmful. It is not suitable for debugging a multi-threaded C++ program, not even for getting backtraces. Please install the package gdb and use the versioned gdb command e.g. gdb7111.