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This patch was aimed at a FIXME in elf32-hppa.c, the ludicrous and confusing fact that non_got_ref after adjust_dynamic_relocs in that backend means precisely the inverse of what it means before adjust_dynamic_relocs. Before, when non_got_ref is set it means there are dynamic relocs, after, if non_got_ref is clear it means "keep dynamic relocs" and later, "has dynamic relocs". There is a reason why it was done that way.. Some symbols that may have dynamic relocations pre-allocated in check_relocs turn out to not be dynamic, and then are not seen by the backend adjust_dynamic_symbols. We want those symbols to lose their dynamic relocs when non-pic, so it's handy that non_got_ref means the opposite after adjust_dynamic_relocs. But it's really confusing. Most other targets, like ppc32, don't always set non_got_ref on non-GOT references that have dynamic relocations. This is because the primary purpose of non_got_ref before adjust_dynamic_relocs is to flag symbols that might need to be copied to .dynbss, and there are relocation types that may require dyn_relocs but clearly cannot have symbols copied into .dynbss, for example, TLS relocations. Why do we need a flag after adjust_dynamic_relocs to say "keep dynamic relocations"? Well, you can discard most unwanted dyn_relocs in the backend adjust_dynamic_relocs, and for those symbols that aren't seen by the backend adjust_dynamic_relocs, in allocate_dynrelocs based on a flag set by adjust_dynamic relocs, dynamic_adjusted. That doesn't solve all our difficulties though. relocate_section needs to know whether a symbol has dyn_relocs, and many targets transfer dyn_relocs to a weakdef if the symbol has one. The transfer means relocate_section can't test dyn_relocs itself and the weakdef field has been overwritten by that time. So non_got_ref is used to flag "this symbol has dynamic relocations" for relocate_section. Confused still? Well, let's hope the comments I've added help clarify things.. The patch also fixes a case where we might wrongly emit dynamic relocations in an executable for common and undefined symbols. * elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol): Set non_got_ref to keep dyn_relocs, clear to discard. Comment. (allocate_dynrelocs): Always clear non_got_ref when clearing dyn_relocs in non-pic case. Invert non_got_ref test. Also test dynamic_adjusted and ELF_COMMON_DEF_P. Move code deleting dyn_relocs on undefined syms to handle for non-pic too. (elf32_hppa_relocate_section): Simplify test for non-pic dyn relocs. * elf32-ppc.c (ppc_elf_adjust_dynamic_symbol): Set non_got_ref to keep dyn_relocs, clear to discard. Comment. (allocate_dynrelocs): Always clear non_got_ref when clearing dyn_relocs in non-pic case. Invert non_got_ref test. Also test dynamic_adjusted and ELF_COMMON_DEF_P. Move code deleting dyn_relocs on undefined syms to handle for non-pic too. (ppc_elf_relocate_section): Simplify test for non-pic dyn relocs. * elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol): Discard dyn_relocs here. Don't bother setting non_got_ref. Comment. (allocate_dynrelocs): Delete special handling of non-pic ELFv2 ifuncs. Move code deleting dyn_relocs on undefined symbols to handle for non-pic too. Don't test non_got_ref. Do test dynamic_adjusted and ELF_COMMON_DEF_P.
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.