Issue with libtool while building/linking fontconfig

Hi,

When building/linking fontconfig, I hit the following problem:

=======================================================================
/bin/bash ../libtool --tag=CC --mode=link /usr/local/uclibc-0.9.28-2/arm//bin/arm-linux-gcc -Os -I/home/thomas/local/buildroot/build_arm/staging_dir/include -I/home/thomas/local/buildroot/build_arm/staging_dir/usr/include -I/usr/local/uclibc-0.9.28-2/arm//arm-linux/include -g -O2 -L/home/thomas/local/buildroot/build_arm/staging_dir/lib -L/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib -o fc-cache fc-cache.o ../src/libfontconfig.la
/usr/local/uclibc-0.9.28-2/arm//bin/arm-linux-gcc -Os -I/home/thomas/local/buildroot/build_arm/staging_dir/include -I/home/thomas/local/buildroot/build_arm/staging_dir/usr/include -I/usr/local/uclibc-0.9.28-2/arm//arm-linux/include -g -O2 -o fc-cache fc-cache.o -L/home/thomas/local/buildroot/build_arm/staging_dir/lib -L/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib ../src/.libs/libfontconfig.so -Wl,--rpath -Wl,/home/thomas/local/buildroot/build_arm/fontconfig-2.6.0/src/.libs
/usr/local/uclibc-0.9.28-2/arm/lib/gcc/arm-linux-uclibc/3.4.5/../../../../arm-linux-uclibc/bin/ld.real: warning: libfreetype.so.6, needed by ../src/.libs/libfontconfig.so, not found (try using -rpath or -rpath-link)
/usr/local/uclibc-0.9.28-2/arm/lib/gcc/arm-linux-uclibc/3.4.5/../../../../arm-linux-uclibc/bin/ld.real: warning: libexpat.so.1, needed by ../src/.libs/libfontconfig.so, not found (try using -rpath or -rpath-link)
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_PS_Font_Info'
../src/.libs/libfontconfig.so: undefined reference to `FT_Init_FreeType'
../src/.libs/libfontconfig.so: undefined reference to `XML_SetElementHandler'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Sfnt_Name'
../src/.libs/libfontconfig.so: undefined reference to `FT_Load_Glyph'
../src/.libs/libfontconfig.so: undefined reference to `FT_Done_Face'
../src/.libs/libfontconfig.so: undefined reference to `XML_SetDoctypeDeclHandler'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Char_Index'
../src/.libs/libfontconfig.so: undefined reference to `XML_ParserFree'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Sfnt_Table'
../src/.libs/libfontconfig.so: undefined reference to `FT_Has_PS_Glyph_Names'
../src/.libs/libfontconfig.so: undefined reference to `XML_SetCharacterDataHandler'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Glyph_Name'
../src/.libs/libfontconfig.so: undefined reference to `FT_Select_Charmap'
../src/.libs/libfontconfig.so: undefined reference to `XML_ErrorString'
../src/.libs/libfontconfig.so: undefined reference to `XML_ParseBuffer'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Next_Char'
../src/.libs/libfontconfig.so: undefined reference to `FT_Load_Sfnt_Table'
../src/.libs/libfontconfig.so: undefined reference to `XML_ParserCreate'
../src/.libs/libfontconfig.so: undefined reference to `FT_Done_FreeType'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_Sfnt_Name_Count'
../src/.libs/libfontconfig.so: undefined reference to `FT_Select_Size'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_X11_Font_Format'
../src/.libs/libfontconfig.so: undefined reference to `XML_SetUserData'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_BDF_Property'
../src/.libs/libfontconfig.so: undefined reference to `XML_GetErrorCode'
../src/.libs/libfontconfig.so: undefined reference to `FT_Get_First_Char'
../src/.libs/libfontconfig.so: undefined reference to `XML_GetBuffer'
../src/.libs/libfontconfig.so: undefined reference to `FT_New_Face'
../src/.libs/libfontconfig.so: undefined reference to `XML_GetCurrentLineNumber'
collect2: ld returned 1 exit status
=======================================================================

The ../src/.libs/libfontconfig.so properly references the .la files of libexpat and libfreetype. If I had these path to the .la files to the big libtool command line, then it links properly.

Any clue about this problem ?

libtool really drives me crazy.

Thanks,

Thomas

Thomas Petazzoni, Free Electrons
Kernel, drivers and embedded Linux development,
consulting, training and support.
http://free-electrons.com

Le Tue, 7 Oct 2008 16:56:10 +0200,
Thomas Petazzoni <[email protected]> a ?crit :

BTW, it was not obvious in my original post, but of course, I hit this problem while trying to compile fontconfig in Buildroot. Otherwise, I wouldn't be posting a mail to this list.

Thanks,

Thomas

Thomas Petazzoni, Free Electrons
Kernel, drivers and embedded Linux development,
consulting, training and support.
http://free-electrons.com

Le Tue, 7 Oct 2008 16:56:10 +0200,
Thomas Petazzoni <[email protected]> a ?crit :

It seems that the problem is caused by libtool configuration variable "link_all_deplibs" being set to "no".

This problem has been reported here:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=297726. It seems that setting link_all_deplibs to yes works for native compilation, but not from cross-compilation. The patch seems be to be Debian-specific, and I'm an Ubuntu user, so I inherited this patch.

As a quick and gory hack, I modified the configure to replace all instances of link_all_deplibs=no by link_all_deplibs=yes. And the compilation now works properly.

What's the proper way of fixing this ?

Thanks,

Thomas

Thomas Petazzoni, Free Electrons
Kernel, drivers and embedded Linux development,
consulting, training and support.
http://free-electrons.com

Hi

[ Not sure it's worth posting to this list about Buildroot problems
since no-one cares, but anyway... ]

Le Thu, 9 Oct 2008 11:43:43 +0200,
Thomas Petazzoni <[email protected]> a ?crit :

This workaround works but is not nice, because the binary ends up being linked with *all* libraries, and not only the ones on which the binary directly depends. This is sad because the Linux dynamic library loader is able at runtime to compute the indirect dependencies. And not being linked with *all* the dependent libraries has the nice effect that you don't need to relink all your applications when you change a library.

So, back to the problem. The following libtool command line:

/bin/bash ../libtool --tag=CC --mode=link /usr/local/uclibc-0.9.29/arm/usr//bin/arm-linux-gcc -Os -I/home/thomas/local/buildroot/build_arm/staging_dir/include -I/home/thomas/local/buildroot/build_arm/staging_dir/usr/include -I/usr/local/uclibc-0.9.29/arm/usr//arm-linux/include -g -O2 -L/home/thomas/local/buildroot/build_arm/staging_dir/lib -L/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib -o fc-cache fc-cache.o ../src/libfontconfig.la mkdir .libs

generates the following command line:

/usr/local/uclibc-0.9.29/arm/usr//bin/arm-linux-gcc -Os -I/home/thomas/local/buildroot/build_arm/staging_dir/include -I/home/thomas/local/buildroot/build_arm/staging_dir/usr/include -I/usr/local/uclibc-0.9.29/arm/usr//arm-linux/include -g -O2 -o fc-cache fc-cache.o -L/home/thomas/local/buildroot/build_arm/staging_dir/lib -L/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib ../src/.libs/libfontconfig.so -Wl,--rpath -Wl,/home/thomas/local/buildroot/build_arm/fontconfig-2.6.0/src/.libs

This command line properly includes a -Wl,--rpath option to the place where the fontconfig library is present (since it hasn't already been installed), but misses a -Wl,--rpath to the usr/lib directory in the staging dir. Manually linking with the same command line, to which "-Wl,--rpath -Wl,/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib" works properly. And the resulting binary only depends on libc and libfontconfig, not on the libraries required by libfontconfig (which will be loaded automatically by the Linux library loader) :

$ arm-linux-readelf -a fc-cache
[...]
 0x00000001 (NEEDED)                     Shared library: [libfontconfig.so.1]
 0x00000001 (NEEDED)                     Shared library: [libc.so.0]
 0x0000000f (RPATH)                      Library rpath: [/home/thomas/local/buildroot/build_arm/fontconfig-2.6.0/src/.libs:/home/thomas/local/buildroot/build_arm/staging_dir/usr/lib/]
[...]

However, the rpath (in which the dynamic linker will try at runtime to find the libraries) has been written in the binary. Which is just plain stupid because this rpath will be completely meaningless on the target system. No rpath is needed since on the target system, the libraries are installed in the standard directories (/lib, /usr/lib), and the dynamic linker knows about these standard paths.

The solution is to use -Wl,--rpath-link instead of -Wl,--rpath.

So, I have a manual workaround, but I don't know how to fix it properly ?

Any clue ?

Thanks a lot,

Thomas

Thomas Petazzoni, Free Electrons
Kernel, drivers and embedded Linux development,
consulting, training and support.
http://free-electrons.com