This repository is for when you don't want something as heavy as crosstool-ng or buildroot. You just need to cross-compile and statically link a few binaries, for example gdbserver, and you have musl/uClibc/glibc toolchain to work from already built. This focuses on gdb-7.12, but you can use these scripts in one form or another when building just about anything, though you will need to modify them from time to time to suit your needs. While they function out of the box for my needs, it is best you think of them as living documentation / reference material for a simpleish task that can be confusing for first-timers, and slow for veterans
* [activate-openwrt-toolchain.env](https://github.com/mzpqnxow/gdb-static-cross/blob/master/activate-script-helpers/activate-openwrt-toolchain.env) - place file in prebuilt OpenWRT toolchain root, source it for productivity, etc.
* [activate-musl-toolchain.env](https://github.com/mzpqnxow/gdb-static-cross/blob/master/activate-script-helpers/activate-musl-toolchain.env) - place file in musl-cross-make toolchain root, source it for productivity, etc.
* [gdbserver-7.12-static-build.sh](https://github.com/mzpqnxow/gdb-static-cross/blob/master/gdbserver-7.12-static-build.sh) - shell script to build a static gdb-7.12 gdbserver using a cross-compile toolchain. Should be executed from gdb-7.12-/gdb/gdbserver/ which is extracted from the [gdbserver-7.12.tar.gz](https://ftp.gnu.org/gnu/gdb/gdb-7.12.1.tar.gz) tarball from GNU distribution sites or from this repository
***If you just want to download a statically linked gdbserver for a specific MIPS(EL) or ARM platform, check the [prebuilt](https://github.com/mzpqnxow/gdb-static-cross/tree/master/prebuilt/) directory***
I tried to compile builds as portable as possible (i.e. emulating FP in software) and got a lot out of use of what was produced in real life situations, so you should find them somewhat reliable on Linux based embedded devices
Some open source projects have no real build system, and many have very strange custom build systems that don't use the "standard" `./configure && make && make install` style build system . You can check out [embedded-toolkt](https://github.com/mzpqnxow/embedded-toolkit) and look in the [src](https://github.com/mzpqnxow/embedded-toolkit/tree/master/src) directory for examples of using these scripts before building various tools such as *gawk*, *gdbserver*, *tcpdump*, *libpcap*, *lsof*, *etc* which have some unique build systems, especially lsof... WTF lsof? Also, if you have a toolchain without wchar, use mawk instead of gawk. The mawk source and patches to build mawk are also included in [src](https://github.com/mzpqnxow/embedded-toolkit/tree/master/src/mawk). You can also use this for simple `gcc bah.c -o bah` operations or `gcc bah.s -o bah`
To use `activate-openwrt-toolchain.env` with a pre-built **OpenWrt Toolchain** you can follow these simple steps. First browse to [https://downloads.openwrt.org/snapshots/trunk/](https://downloads.openwrt.org/snapshots/trunk/) to find the toolchain you want to use. You can use `gcc -v` to determine if the options are right for your CPU
To use this script, assume you have a directory called /toolchains/ and that this is where you will keep the toolchains, one subdirectory per toolchain. To get a new toolchain up in such a way to use active-openwrt-toolchain, grab a file like [OpenWrt-Toolchain-brcm63xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2](https://downloads.openwrt.org/snapshots/trunk/brcm63xx/generic/OpenWrt-Toolchain-brcm63xx-generic_gcc-5.3.0_musl-1.1.16.Linux-x86_64.tar.bz2)
## MUSL via [musl-cross-make](https://github.com/richfelker/musl-cross-make/): Use `source activate-musl-toolchain.env` with an installed toolchain built by musl-cross-make
Using [musl-cross-make](https://github.com/richfelker/musl-cross-make/) is a great experience and kudos to [@richfelker](https://github.com/richfelker) for making it available. I recommend you try it, even just for testing a sample i486 toolchain, useful for building statically linked libraries for common desktop/server platforms. If you do try it, all you need to do is edit the musl-cross-make config.mak file to specify the architecture and any other flags as well as installation path and then use make -j and make install. That's it. You're done. The activate-musl-toolchain file provided here is for you to place in the root of the installed toolchain to use as a convenience to "activate" the toolchain in your environment for use with *weird* build systems, or for software with no build system at all. You use it by simply `source`ing it in your active shell. Sorry, there is no deactivate. Just start a new shell to restore your environment. Here's an example
Look at the end of each .env file. You will see some variables exported, hopefully intuitively named. Those variables can now be accessed in your shell while building software with your toolchain with no need to adjust paths or locate static libraries. Tools like gcc, ar, as, ld, g++, etc. will also now be in your path and there will be a `cross_configure` alias in the shell to simplify using software packages that utilize `./configure` build systems, just replace `./configure` with `cross_configure`. This is a very simple alias that just includes the `--host` and `--prefix` options set, it's not magic.
*This is not something you will be doing often as with gdbserver you will almost always be using a non-native toolchain. However, I wanted to include an example of how it can be cleanly done in a standard build environment. It assumes glibc, which is not really a good target for building non-trivial statically executables. With a minimal amount of effort you can build a musl toolchain for x86_64 or i486*
#### Find static libraries you will need to link gdbserver with
You will need to make sure you have libstdc++.a and libgcc_eh.a on your system. If you don't know what you're doing, you can just use find. Try using the following:
You should now have a statically compiled GDB 7.12 gdbserver for your native OS. Read on for the cross-compile stuff, which is a little more involved but still pretty simple.
