The patch titled Subject: signal: use BUILD_BUG() instead of _NSIG_WORDS_is_unsupported_size() has been added to the -mm tree. Its filename is signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: signal: use BUILD_BUG() instead of _NSIG_WORDS_is_unsupported_size() Kill _NSIG_WORDS_is_unsupported_size(), use BUILD_BUG() instead. This simplifies the code, avoids the nested-externs warnings, and this way we do not defer the problem to linker. Also, fix the indentation in _SIG_SET_BINOP() and _SIG_SET_OP(). Note: this patch assumes that the code like "if (0) BUILD_BUG();" is valid. If not (say __compiletime_error() is not defined and thus __compiletime_error_fallback() uses a negative array) we should fix BUILD_BUG() and/or BUILD_BUG_ON_MSG(). This code should be fine by definition, this is the documented purpose of BUILD_BUG(). Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Reported-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx> Reviewed-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/signal.h | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff -puN include/linux/signal.h~signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size include/linux/signal.h --- a/include/linux/signal.h~signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size +++ a/include/linux/signal.h @@ -67,7 +67,6 @@ static inline int sigismember(sigset_t * static inline int sigisemptyset(sigset_t *set) { - extern void _NSIG_WORDS_is_unsupported_size(void); switch (_NSIG_WORDS) { case 4: return (set->sig[3] | set->sig[2] | @@ -77,7 +76,7 @@ static inline int sigisemptyset(sigset_t case 1: return set->sig[0] == 0; default: - _NSIG_WORDS_is_unsupported_size(); + BUILD_BUG(); return 0; } } @@ -90,24 +89,23 @@ static inline int sigisemptyset(sigset_t #define _SIG_SET_BINOP(name, op) \ static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \ { \ - extern void _NSIG_WORDS_is_unsupported_size(void); \ unsigned long a0, a1, a2, a3, b0, b1, b2, b3; \ \ switch (_NSIG_WORDS) { \ - case 4: \ + case 4: \ a3 = a->sig[3]; a2 = a->sig[2]; \ b3 = b->sig[3]; b2 = b->sig[2]; \ r->sig[3] = op(a3, b3); \ r->sig[2] = op(a2, b2); \ - case 2: \ + case 2: \ a1 = a->sig[1]; b1 = b->sig[1]; \ r->sig[1] = op(a1, b1); \ - case 1: \ + case 1: \ a0 = a->sig[0]; b0 = b->sig[0]; \ r->sig[0] = op(a0, b0); \ break; \ - default: \ - _NSIG_WORDS_is_unsupported_size(); \ + default: \ + BUILD_BUG(); \ } \ } @@ -128,16 +126,14 @@ _SIG_SET_BINOP(sigandnsets, _sig_andn) #define _SIG_SET_OP(name, op) \ static inline void name(sigset_t *set) \ { \ - extern void _NSIG_WORDS_is_unsupported_size(void); \ - \ switch (_NSIG_WORDS) { \ - case 4: set->sig[3] = op(set->sig[3]); \ - set->sig[2] = op(set->sig[2]); \ - case 2: set->sig[1] = op(set->sig[1]); \ - case 1: set->sig[0] = op(set->sig[0]); \ + case 4: set->sig[3] = op(set->sig[3]); \ + set->sig[2] = op(set->sig[2]); \ + case 2: set->sig[1] = op(set->sig[1]); \ + case 1: set->sig[0] = op(set->sig[0]); \ break; \ - default: \ - _NSIG_WORDS_is_unsupported_size(); \ + default: \ + BUILD_BUG(); \ } \ } _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are fs-proc-task_mmuc-dont-use-task-mm-in-m_start-and-show_map.patch fs-proc-task_mmuc-unify-simplify-do_maps_open-and-numa_maps_open.patch proc-introduce-proc_mem_open.patch fs-proc-task_mmuc-shift-mm_access-from-m_start-to-proc_maps_open.patch fs-proc-task_mmuc-shift-mm_access-from-m_start-to-proc_maps_open-checkpatch-fixes.patch fs-proc-task_mmuc-simplify-the-vma_stop-logic.patch fs-proc-task_mmuc-simplify-the-vma_stop-logic-checkpatch-fixes.patch fs-proc-task_mmuc-cleanup-the-tail_vma-horror-in-m_next.patch fs-proc-task_mmuc-shift-priv-task-=-null-from-m_start-to-m_stop.patch fs-proc-task_mmuc-kill-the-suboptimal-and-confusing-m-version-logic.patch fs-proc-task_mmuc-simplify-m_start-to-make-it-readable.patch fs-proc-task_mmuc-introduce-m_next_vma-helper.patch fs-proc-task_mmuc-reintroduce-m-version-logic.patch fs-proc-task_mmuc-update-m-version-in-the-main-loop-in-m_start.patch fs-proc-task_nommuc-change-maps_open-to-use-__seq_open_private.patch fs-proc-task_nommuc-change-maps_open-to-use-__seq_open_private-fix.patch fs-proc-task_nommuc-shift-mm_access-from-m_start-to-proc_maps_open.patch fs-proc-task_nommuc-shift-mm_access-from-m_start-to-proc_maps_open-checkpatch-fixes.patch fs-proc-task_nommuc-dont-use-priv-task-mm.patch proc-maps-replace-proc_maps_private-pid-with-struct-inode-inode.patch proc-maps-make-vm_is_stack-logic-namespace-friendly.patch prctl-pr_set_mm-introduce-pr_set_mm_map-operation-v4.patch mempolicy-change-alloc_pages_vma-to-use-mpol_cond_put.patch mempolicy-change-get_task_policy-to-return-default_policy-rather-than-null.patch mempolicy-sanitize-the-usage-of-get_task_policy.patch mempolicy-remove-the-task-arg-of-vma_policy_mof-and-simplify-it.patch mempolicy-introduce-__get_vma_policy-export-get_task_policy.patch mempolicy-fix-show_numa_map-vs-exec-do_set_mempolicy-race.patch mempolicy-kill-do_set_mempolicy-down_writemm-mmap_sem.patch mempolicy-unexport-get_vma_policy-and-remove-its-task-arg.patch signal-use-build_bug-instead-of-_nsig_words_is_unsupported_size.patch coredump-add-%i-%i-in-core_pattern-to-report-the-tid-of-the-crashed-thread.patch ipc-shm-kill-the-historical-wrong-mm-start_stack-check.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html