Announcing pts-xstatic: A tool for creating small, statically linked Linux i386 executables with any compiler

This blog post announces pts-xstatic, a convenient wrapper tool for compiling and creating portable, statically linked Linux i386 executables. It works on Linux i386 and Linux x86_64 host systems. It wraps an existing compiler (GCC or Clang) of your choice, and it links against uClibc and the other base libraries included in the pts-xstatic binary release.

See the most recent README for all details.

C compilers supported: gcc-4.1 ... gcc-4.8, clang-3.0 ... clang-3.3. C++ compilers supported: g++ and clang++ corresponding to the supported C compilers. Compatible uClibc C and C++ headers (.h) and precompiled static libraries (e.g. libc.a, libz.a, libstdc++.a) are also provided by pts-xstatic. To minimize system dependencies, pts-xstatic can compile with pts-clang (for both C and C++), which is portable, and you can install it as non-root.

As an alternative of pts-xstatic, if you want a tiny, self-contained (single-file) for Linux i386, please take a look at pts-tcc. With pts-xstatic, you can create faster and smaller statically linked executables, with the compiler of your choice.

As an alternative for pts-xstatic and uClibc, see diet libc and its diet tool (which is an alternative of the xstatic tool), with which you can create even smaller binaries.

Motivation

0. Available uClibc GCC toolchain binary releases are very old, e.g. the i686 release contains gcc-4.1.2 compiled on 2009-04-11.
1. With uClibc Buildroot, the uClibc version is tied to a specific GCC version. It's not possible to compile with your favorite preinstalled C or C++ compiler version, and link against your favorite uClibc version. pts-xstatic makes this possible.
2. libstdc++ is not easily available for uClibc, and it's a bit cumbersome to compile. pts-xstatic contains a precompiled version.

Minimum installation

If you want to install try pts-xstatic quickly, without root access, without installing any dependencies, and without changing any settings, this is the easiest way:

$ cd /tmp
$ rm -f pts-xstatic-latest.sfx.7z
$ wget http://pts.50.hu/files/pts-xstatic/pts-xstatic-latest.sfx.7z
$ chmod +x pts-xstatic-latest.sfx.7z
$ ./pts-xstatic-latest.sfx.7z -y  # Creates the pts-xstatic directory.
$ rm -f pts-clang-latest.sfx.7z
$ wget http://pts.50.hu/files/pts-clang/pts-clang-latest.sfx.7z
$ chmod +x pts-clang-latest.sfx.7z
$ ./pts-clang-latest.sfx.7z -y  # Creates the pts-clang directory.
$ cat >>hw.c <<'END'
#include <stdio.h>
int main(void) {
  return !printf("Hello, %s!\n", "World");
}
END
$ pts-xstatic/bin/xstatic pts-clang/bin/clang -s -O2 -W -Wall hw.c && ./a.out
Hello, World!
$ strace -e open ./a.out
Hello, World!
$ file a.out
a.out: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), statically linked, stripped
$ ls -l a.out
-rwxr-xr-x 1 pts pts 16888 Jan  2 23:17 a.out

Compare the file size with statically linking against regular (e)glibc:

$ gcc -static -m32 -o a.big -s -O2 -W -Wall hw.c && ./a.big
Hello, World!
$ strace -e open ./a.big
Hello, World!
$ file a.big
a.big: ELF 32-bit LSB executable, Intel 80386, version 1 (GNU/Linux), statically linked, for GNU/Linux 2.6.24, BuildID[sha1]=0x37284f286ffeecdb7ac5d77bfa83ade4310df098, stripped
$ ls -l a.big
-rwxr-xr-x 1 pts eng 684748 Jan  2 23:20 a.big

FYI with diet libc, the generated a.out file is only 8668 bytes long.

See full installation instructions in the most recent README.

Does pts-xstatic create portable executables?

pts-xstatic creates portable, statically linked, Linux ELF i386 executables, linked against uClibc. By default, these executables don't need any external file (not even the file specified by argv[0], not even the /proc filesystem) to run. NSS libraries (the code needed for e.g. getpwent(3) (getting info of Unix system users) and gethostbyname(3) (DNS resolution)) are also included. The executables also work on FreeBSD in Linux mode if the operating system field in the ELF header frm SYSV to Linux.

As an alternative to pts-xstatic: gcc -static (or clang -static) doesn't provide real portability, because for calls such as getpwent(3) (getting info of Unix system users) and gethostbyname(3) (DNS resolution), glibc loads files such as libnss_compat.so, libnss_dns.so. On the target system those libraries may be incompatible with your binary, so you may get a segfault or unintended behavior. pts-xstatic solves this, because it uses uClibc.

It can be useful to embed locale files, gconv libraries, arbitrary data and configuration files needed by the program, Neither `gcc -static', pts-xstatic or statifier can do it, but Ermine can. Ermine is not free software, but you can get a free-of-charge time-limited trial, and you can ask for a discount for noncommercial use. See all details here, and give it a try!

More info

See the most recent README for full installation instructions, usage details, full feature list etc.