# Building GDB for use with *libgdbs*

As of today, *libgdbs* require a very recent version of GDB. This is because
*libgdbs* requires various patches. Some of them are are already upstreamed
to [GDB's master branch][1], some of them are in process.

Therefore you may need to compile suitable GDB yourself. A git repository with
all the patches can be found at [https://github.com/janvrany/binutils-gdb][2]
*in branch `users/jv/vdb`* (note the branch!)

## Linux

### Preparing build environment

* On *Debian Buster* (tested on as of 2018-11-26)
  ```
  apt-get install build-essential texinfo python3-dev flex bison libexpat-dev libsource-highlight-dev
  ```

* On *Ubuntu 18.04* (tested on as of 2019-03-20)
  ```
  apt-get install g++  make texinfo python3-dev flex bison libfl2 libexpat1-dev
  ```

### Compiling GDB

    git clone --depth=1 https://github.com/janvrany/binutils-gdb
    cd binutils-gdb
    ./configure \
        --disable-werror \
        --with-guile=no \
        --with-python=/usr/bin/python3 \
        --enable-targets="i686-pc-linux-gnu,x86_64-pc-linux-gnu,i686-w64-mingw32,x86_64-w64-mingw32,riscv64-pc-linux-gnu,ppc-pc-linux-gnu"
    make -j4


You may want to tweak target list to fot your needs, the above list includes
both i686 and x86_64 Linux, both i686 and x86_64 Windows,PowerPC and RISC-V 64
Linux.

## Windows using MSYS2 and MINGW64

Following recipe has been tested on Windows 7 and Windows 10 using [MSYS2][3]
and `MinGW 64`.

### Preparing build environment

In order to build GDB from source, you need to install [MSYS2][3] and `MinGW 64`
toolchain:

 * Install [MSYS2][3] from [https://msys2.github.io][3]. Make sure to install
   it to `C:\MSYS64`. Once installer finishes, update packages:
   ```
   C:\msys64\usr\bin\pacman.exe -Sy pacman
   C:\msys64\usr\bin\pacman.exe -Syu
   C:\msys64\usr\bin\pacman.exe -Su
   ```
   Note: during `pacman -Syu` you maybe asked to close command prompt window.
   Don't forget to close it otherwise you will have to start from beginning.

 * Add `C:\msys64\usr\bin` to your `PATH`:
   ```
   setx PATH "%PATH%;c:\msys64\usr\bin"
   ```

 * Install `MinGW 64` toolchain and other dev tools:
   ```
   pacman -S git bison flex texinfo mingw-w64-x86_64-gcc mingw-w64-x86_64-SDL mingw-w64-x86_64-libexpat mingw-w64-x86_64-python3
   ```

### Compiling GDB

    git clone --depth=1 https://github.com/janvrany/binutils-gdb
    cd binutils-gdb
    set "PATH=%PATH%;C:\msys64\mingw64\bin"
    bash configure --build=x86_64-w64-mingw32 --disable-werror --with-system-readline --with-guile=no --with-python=C:\msys64\mingw64\bin\python3 --enable-targets="i686-w64-mingw32,x86_64-w64-mingw32"
    make -j4

If you don't have `C:\msys64\mingw64\bin` in your `PATH` (it is *NOT* by default),
then you may need to copy required libraries along `gdb.exe` otherwise GDB won't
start:

    set "PATH=%PATH%;C:\msys64\mingw64\bin"
    bash -c "for f in gdb/gdb.exe | grep MSYS | cut -d ' ' -f 3); do cp $f gdb ; done"

[1]: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=summary
[2]: https://github.com/janvrany/binutils-gdb
[3]: https://msys2.github.io/