Setup Linux Toolchain from Scratch

[中文]

The following instructions are alternative to downloading binary toolchain from Espressif website. To quickly setup the binary toolchain, instead of compiling it yourself, backup and proceed to section Standard Setup of Toolchain for Linux.

Note

The reason you might need to build your own toolchain is to solve the Y2K38 problem (time_t expand to 64 bits instead of 32 bits).

Install Prerequisites

To compile with ESP-IDF you need to get the following packages:

  • CentOS 7:

    sudo yum install git wget ncurses-devel flex bison gperf python pyserial python-pyelftools cmake ninja-build ccache dfu-util
    
  • Ubuntu and Debian:

    sudo apt-get install git wget libncurses-dev flex bison gperf python python-pip python-setuptools python-serial python-click python-cryptography python-future python-pyparsing python-pyelftools cmake ninja-build ccache libffi-dev libssl-dev dfu-util
    
  • Arch:

    sudo pacman -S --needed gcc git make ncurses flex bison gperf python-pyserial python-click python-cryptography python-future python-pyparsing python-pyelftools cmake ninja ccache dfu-util
    

Note

CMake version 3.5 or newer is required for use with ESP-IDF. Older Linux distributions may require updating, enabling of a “backports” repository, or installing of a “cmake3” package rather than “cmake”.

Compile the Toolchain from Source

  • Install dependencies:

    • CentOS 7:

      sudo yum install gawk gperf grep gettext ncurses-devel python python-devel automake bison flex texinfo help2man libtool make
      
    • Ubuntu pre-16.04:

      sudo apt-get install gawk gperf grep gettext libncurses-dev python python-dev automake bison flex texinfo help2man libtool make
      
    • Ubuntu 16.04 or newer:

      sudo apt-get install gawk gperf grep gettext python python-dev automake bison flex texinfo help2man libtool libtool-bin make
      
    • Debian 9:

      sudo apt-get install gawk gperf grep gettext libncurses-dev python python-dev automake bison flex texinfo help2man libtool libtool-bin make
      
    • Arch:

      TODO
      

Create the working directory and go into it:

mkdir -p ~/esp
cd ~/esp

Download crosstool-NG and build it:

git clone https://github.com/espressif/crosstool-NG.git
cd crosstool-NG
git checkout esp-2020r1
git submodule update --init
./bootstrap && ./configure --enable-local && make

Note

To create a toolchain with support for 64-bit time_t, you need to remove the --enable-newlib-long-time_t option from the crosstool-NG/samples/xtensa-esp32-elf/crosstool.config file in 33 and 43 lines.

Build the toolchain:

./ct-ng xtensa-esp32-elf
./ct-ng build
chmod -R u+w builds/xtensa-esp32-elf

Toolchain will be built in ~/esp/crosstool-NG/builds/xtensa-esp32-elf.

Add Toolchain to PATH

The custom toolchain needs to be copied to a binary directory and added to the PATH.

Choose a directory, for example ~/esp/xtensa-esp32-elf/, and copy the build output to this directory.

To use it, you will need to update your PATH environment variable in ~/.profile file. To make xtensa-esp32-elf available for all terminal sessions, add the following line to your ~/.profile file:

export PATH="$HOME/esp/xtensa-esp32-elf/bin:$PATH"

Note

If you have /bin/bash set as login shell, and both .bash_profile and .profile exist, then update .bash_profile instead. In CentOS, alias should set in .bashrc.

Log off and log in back to make the .profile changes effective. Run the following command to verify if PATH is correctly set:

printenv PATH

You are looking for similar result containing toolchain’s path at the beginning of displayed string:

$ printenv PATH
/home/user-name/esp/xtensa-esp32-elf/bin:/home/user-name/bin:/home/user-name/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

Instead of /home/user-name there should be a home path specific to your installation.

Next Steps

To carry on with development environment setup, proceed to Step 2. Get ESP-IDF.