Reid Spencer 1bc686433b Changes to support cross-compiling LLVM. The GenLibDeps.pl script needs to
have a compile-host version of "nm", not build-host. In order to effect this
we must use autoconf to determine the correct "nm" to use and propagate that
through the makefiles, through llvm-config and finally to GenLibDeps.pl as
an optional argument.
Patch contributed by Anton Korobeynikov. Thanks!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29368 91177308-0d34-0410-b5e6-96231b3b80d8
2006-07-27 23:00:30 +00:00
..
2006-06-01 01:08:28 +00:00

Upgrading Libtool
===============================================================================

If you are in the mood to upgrade libtool, you must do the following:

 1. Get the new version of libtool and put it in <SRC>
 2. configure/build/install libtool with --prefix=<PFX>
 3. Copy <SRC>/ltdl.m4 to llvm/autoconf/m4
 4. Copy <PFX>/share/aclocal/libtool.m4 to llvm/autoconf/m4/libtool.m4
 5. Copy <PFX>/share/libtool/ltmain.sh to llvm/autoconf/ltmain.sh
 6. Run sed -e 's/output.exp/outputname.exp/g' on ltmain.sh
 7. Copy <PFX>/share/libtool/libltdl/ltdl.c to llvm/lib/System
 8. Copy <PFX>/share/libtool/libltdl/ltdl.h to llvm/lib/System
 9. Adjust the llvm/autoconf/m4/libtool.m4 file to ensure that the variable
    default_ofile is set to "mklib" instead of "libtool"
10. Run "autoupdate libtool.m4 ltdl.m4" in the llvm/autoconf/m4 directory.
    This should correctly update the macro definitions in the libtool m4 
    files to match the version of autoconf that LLVM uses. This converts
    AC_HELP_STRING to AS_HELP_STRING and AC_TRY_LINK to AC_LINK_IFELSE, amongst
    other things. You may need to manually adjust the files.
11. Run AutoRegen.sh to get the new macros into configure script
12. If there are any warnings from configure, go to step 9.
13. Rebuild LLVM, making sure it reconfigured
14. Test the JIT which uses libltdl
15. If it all works, only THEN commit the changes.

Upgrading autoconf
===============================================================================

If you are in the mood to upgrade autoconf, you should:

 1. Consider not upgrading.
 2. No really, this is a hassle, you don't want to do it.
 3. Get the new version of autoconf and put it in <SRC>
 4. configure/build/install autoconf with --prefix=<PFX>
 5. Run autoupdate on all the m4 macros in llvm/autoconf/m4
 6. Run autoupdate on llvm/autoconf/configure.ac
 7. Regenerate configure script with AutoRegen.sh
 8. If there are any warnings from autoconf, fix them and go to step 7.
 9. Test, test, test.