Tips to obtain a very small static elinks binary

Tips to obtain a very small static elinks binary suitable for mini distributions

Remove config.cache (previous CC may be cached):

$ rm config.cache

Use dietlibc (http://www.fefe.de/dietlibc/) or similar stuff (uClibc, …):

$ export CC='diet -Os gcc'

Use compilers flags to optimize for size:

$ export CFLAGS='-s -fno-inline -nostdinc -fomit-frame-pointer'

Note that if you don't use dietlibc, you definitively want to add -Os or -O2 to CFLAGS; GCC 2.95 does not know -Os, and some say -O2 gives smaller executables even for GCC 3.x.

Tip

If you use these CFLAGS on Cygwin and you get unresolved symbols (htons and suite in particular), try removing -fno-inline parameter.

Disable some compile-time options:

$ ./configure --disable-ipv6 --disable-backtrace --disable-nls \
  --enable-fastmem --without-zlib --without-bzlib --disable-xbel \
  --without-lua --without-gnutls --without-openssl --without-x \
  --enable-small --without-spidermonkey --without-gpm

You can disable bookmarks, globhist and more, too, if you want to.

Other configure options that can reduce the size

  • --disable-backtrace disables internal backtrace code.
  • --disable-nls disables i18n support.
  • --enable-fastmem disables internal malloc() debugging and use alloca() wherever possible.
  • --enable-small forces to remove some text descriptions in options and keybind stuff (regain 30Kb).

Dependencies over external libs must be removed using the related configure options:

Option Description
--without-zlib removes libz dependency (compression)
--without-bzlib removes libbz2 dependency (compression)
--disable-xbel removes expat dependency (XBEL bookmarks support)
--without-lua removes liblua dependency (Lua scripting)
--without-gnutls removes libtls dependency (SSL support)
--without-openssl removes libssl dependency (SSL support)
--without-x removes libx11 dependency (restoring terminal title)
--without-spidermonkey removes libjs dependency (JavaScript)
--without-gpm removes libgpm dependency (mouse/console)

It seems GCC 2.95.x do not generate as small binaries as GCC 3.2.x with same flags.

You can use an executable compressor like UPX http://upx.sourceforge.net/.

Here are some results using gcc 2.95.3, dietlibc-0.23, and previous flags:

me$ ls -l src/elinks
-rwxr-xr-x   1 zas      users      495100 Oct 20 15:53 src/elinks
me$ upx --best src/elinks
me$ ls -l src/elinks
-rwxr-xr-x   1 zas      users      217946 Oct 20 15:53 src/elinks

Whow ! Around 200kb :)

Details about the --enable-small configure option effects:

  • it disables long descriptions of options;
  • it disables textual descriptions of keybinding options;
  • it reduces size of some HTTP errors messages;
  • it disables fastfind feature, reducing performance, but also reducing a lot memory usage, and a bit the executable size.