[Bug translator/4186] Cross compiling for sub architectures (e.g. i586 target i686 host) fails

[wcohen at redhat dot com]

------- Additional Comments From wcohen at redhat dot com  2007-03-20 20:40 -------
It looks like the correct code subarchitecture code should be
generated.  An automated grep of the files in the linux kernel
directory turned up the following line:

./arch/i386/Makefile.cpu:cflags-$(CONFIG_M586)          += -march=i586

One of the problems observed in the stap translator code is that
tapsets.cxx:query_module() assumes that if the vmlinux file is i386
that it should be i686. It could be i586 or i486. There is a comment
in there about this:

      // Validate the machine code in this elf file against the
      // session machine.  This is important, in case the wrong kind
      // of debuginfo is being automagically processed by elfutils.
      // Unfortunately, while we can tell i686 apart from x86-64,
      // we can't help confusing i586 vs i686 (both EM_386).


The translator should be able to do a better job determine the target
architecture.  Couldn't this information be obtained from .config and
Makefile in kernel-devel?

For cross compiling http://lwn.net/Articles/21823/ has comments about
building modules and cross-compile. Should be able to do the following
when building the systemtap module:

CROSS_COMPILE=ppc_4xx- make -C ...


-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=4186

------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.