The definition of target hooks is spread across multiple files, which makes it hard to add new or modify existing target hooks in a consistent manner.
Indeed. A serious issue.
A patch is here: http://gcc.gnu.org/ml/gcc-patches/2010-05/msg00788.html
(In reply to comment #2) updated patch for revision 159828: http://gcc.gnu.org/ml/gcc-patches/2010-05/msg01938.html
(In reply to comment #3) updated patch for revision 160389: http://gcc.gnu.org/ml/gcc-patches/2010-06/msg00665.html
(In reply to comment #4) updated patch for revision 160454: http://gcc.gnu.org/ml/gcc-patches/2010-06/msg00846.html
Subject: Bug 44034 Author: amylaar Date: Tue Jun 29 18:22:00 2010 New Revision: 161547 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=161547 Log: gcc: PR other/44034 * target.def, doc/tm.texi.in, genhooks.c: New files. * target.h: Instead of defining individual hook members, define DEFHOOKPOD / DEFHOOK / DEFHOOK_UNDOC / HOOKSTRUCT and include target.def. * target-def.h: Instead of defining individual hook initializers, include target-hooks-def.h. * df-scan.c, haifa-sched.c, sel-sched.c: Rename targetm members: targetm.live_on_entry -> targetm.extra_live_on_entry targetm.sched.md_finish ->targetm.sched.finish targetm.sched.md_init -> targetm.sched.init targetm.sched.md_init_global -> targetm.sched.init_global targetm.asm_out.unwind_label -> targetm.asm_out.emit_unwind_label targetm.asm_out.except_table_label -> targetm.asm_out.emit_except_table_label targetm.asm_out.visibility -> targetm.asm_out.assemble_visibility targetm.target_help -> targetm.help targetm.vectorize.builtin_support_vector_misalignment -> targetm.vectorize.support_vector_misalignment targetm.file_start_app_off -> targetm.asm_file_start_app_off targetm.file_start_file_directive -> targetm.asm_file_start_file_directive * dwarf2out.c, opts.c, tree-vect-data-refs.c, except.c: Likewise. * varasm.c, config/alpha/alpha.c, config/cris/cris.c: Likewise. * gcc/config/spu/spu.c, config/ia64/ia64.c: Rename target macros: TARGET_VECTOR_ALIGNMENT_REACHABLE -> TARGET_VECTORIZE_VECTOR_ALIGNMENT_REACHABLE TARGET_SUPPORT_VECTOR_MISALIGNMENT -> TARGET_VECTORIZE_SUPPORT_VECTOR_MISALIGNMENT TARGET_UNWIND_EMIT -> TARGET_ASM_UNWIND_EMIT * config/rs6000/rs6000.c, config/arm/arm.c: Likewise. * Makefile.in (TARGET_H): Depend on target.def. (TARGET_DEF_H): Depend on target-hooks-def.h. (target-hooks-def.h, tm.texi, s-target-hooks-def-h): New rules. (s-tm-texi, build/genhooks.o, build/genhooks): Likewise. * doc/tm.texi: Regenerate. gcc/c-family: * c-common.c: Rename targetm member: targetm.enum_va_list -> targetm.enum_va_list_p gcc/po: * EXCLUDES: Add genhooks.c. Index: gcc/doc/tm.texi Added: trunk/gcc/doc/tm.texi.in - copied, changed from r161540, trunk/gcc/doc/tm.texi trunk/gcc/genhooks.c trunk/gcc/target.def Modified: trunk/gcc/ChangeLog trunk/gcc/Makefile.in trunk/gcc/c-family/ChangeLog trunk/gcc/c-family/c-common.c trunk/gcc/config/alpha/alpha.c trunk/gcc/config/arm/arm.c trunk/gcc/config/cris/cris.c trunk/gcc/config/ia64/ia64.c trunk/gcc/config/rs6000/rs6000.c trunk/gcc/config/spu/spu.c trunk/gcc/df-scan.c trunk/gcc/doc/tm.texi trunk/gcc/dwarf2out.c trunk/gcc/except.c trunk/gcc/haifa-sched.c trunk/gcc/opts.c trunk/gcc/po/ChangeLog trunk/gcc/po/EXCLUDES trunk/gcc/sel-sched.c trunk/gcc/target-def.h trunk/gcc/target.h trunk/gcc/tree-vect-data-refs.c trunk/gcc/varasm.c
Subject: Bug 44034 Author: iains Date: Wed Jun 30 14:33:40 2010 New Revision: 161606 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=161606 Log: PR other/44034 * config/darwin.c (darwin_override_options): Use renamed targetm.asm_out.emit_unwind_label. Modified: trunk/gcc/ChangeLog trunk/gcc/config/darwin.c
Patch committed to mainline. AFAIK the only lingering issue is this one: http://gcc.gnu.org/ml/gcc-patches/2010-06/msg03046.html (And of course the stuff that needs some help from the FSF - PR44035, PR44033, PR44032)