Hi, thanks for your responses.
I've debugged a little further and found out that the testcase breakage was caused by (the elfos.h part): http://gcc.gnu.org/ml/gcc-patches/2005-04/msg00913.html The elfos.h part of the patch was reverted on 04/14/2005: http://gcc.gnu.org/ml/gcc-patches/2005-04/msg01604.html and since then everything is back working again. As already pointed out in the discussion thread, it is probably not the patch to blame here. It seems that the patch reveals a linker problem. Without the patch reverted I can reproduce the following failure on 31bit (s390) as well as on 64bit (s390x) using binutils-2.15.92.0.2 from kernel.org: /usr/bin/ld: Warning: size of symbol `__gnu_cxx::__common_pool_policy<__gnu_cxx::__pool, true>::_S_get_pool()' changed from 136 in ta.o to 208 in tc.o /usr/bin/ld: Warning: size of symbol `__gnu_cxx::__common_pool_policy<__gnu_cxx::__pool, true>::_S_destroy_thread_key(void*)' changed from 56 in ta.o to 216 in tc.o /usr/bin/ld: Warning: size of symbol `__gnu_cxx::__common_pool_policy<__gnu_cxx::__pool, true>::_S_initialize()' changed from 56 in ta.o to 224 in tc.o /usr/bin/ld: Warning: size of symbol `__gnu_cxx::__common_pool_policy<__gnu_cxx::__pool, true>::_S_initialize_once()' changed from 116 in ta.o to 288 in tc.o The warnings disappear when --parm inline-unit-growth=.. is used to increase the treshold. But you are right that they can also be triggered using different optimization levels. So I agree that the linker should be able to sort this out. Without the patch the symbols above are marked as "weak" in both object files. With the patch both are "global"._bfd_elf_merge_symbol in binutils wants to see one of them to be "weak" in order to accept a different size. Because both of the symbols are in comdat .group sections and therefore are explicitly supposed to be merged the linker should accept a size change even if they are marked "global". This is already fixed in the current binutils cvs. Bye, -Andreas-
