Compiling 32-bit GTK+ Applications of 64 bit Linux

Question

I am having some trouble compiling 32-bit GTK+ applications on 64-bit Linux, specifically Ubuntu 10.04. Compiling 64-bit GTK+ applications works fine, and everything is set up to compile 32-bit apps as well, but it doesn't work with GTK+

I have a very simple test program that I am using for trouble shooting that is simply a gtk_init and a gtk_main, which compiles fine as -m64. I am compiling with gcc 4.6.2, calling it with:

gcc -m32 gtktest.c `pkg-config --cflags gtk+-2.0` `pkg-config --libs gtk+-2.0`

These are the two different kinds of error messages I get:

/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.6.2/../../../../x86_64-unknown-linux-gnu/bin/ld: warning: libXext.so.6, needed by /usr/lib/../lib32/libgtk-x11-2.0.so, not found (try using -rpath or -rpath-link)

and

/usr/lib/../lib32/libgdk-x11-2.0.so: undefined reference to `XmbSetWMProperties'

Keep in mind that these aren't the only errors, I just included the two specific types for reference and to keep it short, I get errors for the whole stack of GTK+ libraries.

I do have all of the proper 32-bit versions of the libraries in my lib32 folders.

Hopefull someone has had this problem before and can help me, this is really causing me quite the headaches, and I can't fine much help any where on the net.

Please ask if there is any other information you need me to provide to help with diagnosing this problem.

Note: I do have the ia32-libs and gcc-multilib packages. Ubuntu 10.04 does not have a separate ia32-libs-gtk packages, but I think these are wrapped in to the ia32-libs packages. They all are present on my system.

I think this must be some sort of linker config problem. I've recently built the new Free Pascal compiler and a 32 bit cross compiler, and I also upgraded GCC to 4.6.2 to take advantage of some of the new C++ features and fixes to C99 support. The default 4.4.3 GCC still exists on my system. Where I think the problem has been introduced is when I installed a new binutils because I've been experimenting with Clang and LLVM as a toolchain, and I wanted and ld with plug-in capabilities, so I figured might as well upgrade them all.

Everything works fine compiling 64 bit programs, there hasn't been a single problem with the new tools at all, and I can compile 32-bit programs but when it comes time to explicitly link something in I have problems.

I know my current set of libs is appropriate, and I have Free Basic installed which only emits 32 bit code, and I was able to build 32-bit GTK+ programs no problem before this upgrade.

Just wondering if anyone has any ideas what configs might have been changed in this upgrade or has had this happen to them before? I really should upgrade to a newer distro so I can take advantage of all the new software with out have to hack up all of my packages, but unfortunatly there is a bug in the newer kernels that prevents my computer from coming back from standby, and this is a laptop I use for personal side projects, so proper power management is pretty important, and it's not a huge loss if I bork the system, other than I have it set up pretty much perfect for my workflow.

Answer 1

this work on my Debian 11 with multiarch gtk3-dev:i386 installed

$ export PKG_CONFIG_PATH=/usr/lib/i386-linux-gnu/pkgconfig; pkg-config --cflags gtk+-3.0

Answer 2

You may tell pkg-config to search for the 32-bit libraries with the environment variable PKG_CONFIG_PATH. For Ubuntu:

export PKG_CONFIG_PATH=/usr/lib32/pkgconfig:$PKG_CONFIG_PATH

For Redhat:

export PKG_CONFIG_PATH=/usr/lib/pkgconfig:$PKG_CONFIG_PATH

Answer 3

The GTK package in 12.04 doesn't seem to work correctly with multiarch. You can work around this on Ubuntu 12.04 by creating the following symlinks:

sudo ln -s /lib/i386-linux-gnu/libglib-2.0.so.0 /usr/lib32/libglib-2.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libgtk-x11-2.0.so.0 /usr/lib32/libgtk-x11-2.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libgdk-x11-2.0.so.0 /usr/lib32/libgdk-x11-2.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libatk-1.0.so.0 /usr/lib32/libatk-1.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libpangox-1.0.so.0 /usr/lib32/libpangox-1.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libpango-1.0.so.0 /usr/lib32/libpango-1.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libgmodule-2.0.so.0 /usr/lib32/libgmodule-2.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libgobject-2.0.so.0 /usr/lib32/libgobject-2.0.so
sudo ln -s /usr/lib/i386-linux-gnu/libgdk_pixbuf-2.0.so.0 /usr/lib32/libgdk_pixbuf-2.0.so

I found the answer in this thread: http://www.blitzbasic.com/Community/posts.php?topic=101357

Alternatively (probably better), you can leave the base system untouched and update your link to search by file name instead of library name. Something like:

gcc -m32 gtktest.c `pkg-config --cflags gtk+-2.0` -L/usr/lib/i386-linux-gnu -l:libgio-2.0.so.0 ...

This isn't great. You'll have to add a -l: for each library that the linker can't find and your build will break if the library file name ever changes.

Answer 4

I think you need to install the ia32-libs-gtk & gcc-multilib packages, and you need to compile and link with gcc -m32 as you already do.