diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 14 | ||||
| -rw-r--r-- | gcc/common.opt | 4 | ||||
| -rw-r--r-- | gcc/doc/invoke.texi | 29 | ||||
| -rw-r--r-- | gcc/ipa-pure-const.c | 16 | ||||
| -rw-r--r-- | gcc/opts.c | 5 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/noreturn-4.c | 2 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/noreturn-7.c | 6 | ||||
| -rw-r--r-- | gcc/tree-cfg.c | 18 | ||||
| -rw-r--r-- | gcc/tree-cfgcleanup.c | 18 | ||||
| -rw-r--r-- | gcc/tree-flow.h | 3 |
11 files changed, 82 insertions, 38 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 742950c041b..59f69396a6e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,17 @@ +2010-06-11 Jan Hubicka <jh@suse.cz> + + * doc/invoke.texi (Wsuggest-attribute): Document. + (Wmissing-noreturn): Remove. + * ipa-pure-const.c (warn_function_noreturn): New function. + * opts.c (decode_options): Set warn_suggest_attribute_noreturn on + warn_missing_noreturn. + * common.opt (Wsuggest-attribute=noreturn): New. + * tree-flow.h (warn_function_noreturn): Declare. + * tree-cfg.c (execute_warn_function_noreturn): Use + warn_function_noreturn. + (gate_warn_function_noreturn): New. + (pass_warn_function_noreturn): Update. + 2010-06-11 Manuel López-Ibáñez <manu@gcc.gnu.org> * c-typeck.c (handle_warn_cast_qual): Add loc diff --git a/gcc/common.opt b/gcc/common.opt index a96158237dd..f001e026fc9 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -192,6 +192,10 @@ Wsuggest-attribute=pure Common Var(warn_suggest_attribute_pure) Warning Warn about functions which might be candidates for __attribute__((pure)) +Wsuggest-attribute=noreturn +Common Var(warn_suggest_attribute_noreturn) Warning +Warn about functions which might be candidates for __attribute__((noreturn)) + Wswitch Common Var(warn_switch) Warning Warn about enumerated switches, with no default, missing a case diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 777c3842ab5..3519ead1c59 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -248,7 +248,7 @@ Objective-C and Objective-C++ Dialects}. -Wlogical-op -Wlong-long @gol -Wmain -Wmissing-braces -Wmissing-field-initializers @gol -Wmissing-format-attribute -Wmissing-include-dirs @gol --Wmissing-noreturn -Wno-mudflap @gol +-Wno-mudflap @gol -Wno-multichar -Wnonnull -Wno-overflow @gol -Woverlength-strings -Wpacked -Wpacked-bitfield-compat -Wpadded @gol -Wparentheses -Wpedantic-ms-format -Wno-pedantic-ms-format @gol @@ -3667,16 +3667,17 @@ attributes currently supported are listed below. @opindex Wno-suggest-attribute=pure @opindex Wsuggest-attribute=const @opindex Wno-suggest-attribute=const +@opindex Wsuggest-attribute=noreturn +@opindex Wno-suggest-attribute=noreturn Warn about functions which might be candidates for attributes -@code{pure} or @code{const}. The compiler only warns for functions -visible in other compilation units or if it cannot prove that the -function returns normally. A function returns normally if it doesn't -contain an infinite loop nor returns abnormally by throwing, calling -@code{abort()} or trapping. This analysis requires option -@option{-fipa-pure-const}, which is enabled by default at @option{-O} -and higher. Higher optimization levels improve the accuracy of the -analysis. +@code{pure}, @code{const} or @code{noreturn}. The compiler only warns for +functions visible in other compilation units or (in the case of @code{pure} and +@code{const}) if it cannot prove that the function returns normally. A function +returns normally if it doesn't contain an infinite loop nor returns abnormally +by throwing, calling @code{abort()} or trapping. This analysis requires option +@option{-fipa-pure-const}, which is enabled by default at @option{-O} and +higher. Higher optimization levels improve the accuracy of the analysis. @end table @item -Warray-bounds @@ -4153,16 +4154,6 @@ struct s x = @{ .f = 3, .g = 4 @}; This warning is included in @option{-Wextra}. To get other @option{-Wextra} warnings without this one, use @samp{-Wextra -Wno-missing-field-initializers}. -@item -Wmissing-noreturn -@opindex Wmissing-noreturn -@opindex Wno-missing-noreturn -Warn about functions which might be candidates for attribute @code{noreturn}. -Note these are only possible candidates, not absolute ones. Care should -be taken to manually verify functions actually do not ever return before -adding the @code{noreturn} attribute, otherwise subtle code generation -bugs could be introduced. You will not get a warning for @code{main} in -hosted C environments. - @item -Wmissing-format-attribute @opindex Wmissing-format-attribute @opindex Wno-missing-format-attribute diff --git a/gcc/ipa-pure-const.c b/gcc/ipa-pure-const.c index 766c8fc6456..da8d442107b 100644 --- a/gcc/ipa-pure-const.c +++ b/gcc/ipa-pure-const.c @@ -177,6 +177,16 @@ warn_function_const (tree decl, bool known_finite) = suggest_attribute (OPT_Wsuggest_attribute_const, decl, known_finite, warned_about, "const"); } + +void +warn_function_noreturn (tree decl) +{ + static struct pointer_set_t *warned_about; + if (!lang_hooks.missing_noreturn_ok_p (decl)) + warned_about + = suggest_attribute (OPT_Wsuggest_attribute_noreturn, decl, + true, warned_about, "noreturn"); +} /* Init the function state. */ static void @@ -1514,11 +1524,7 @@ local_pure_const (void) if (!skip && !TREE_THIS_VOLATILE (current_function_decl) && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0) { - if (warn_missing_noreturn - && !lang_hooks.missing_noreturn_ok_p (cfun->decl)) - warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn, - "function might be possible candidate " - "for attribute %<noreturn%>"); + warn_function_noreturn (cfun->decl); if (dump_file) fprintf (dump_file, "Function found to be noreturn: %s\n", lang_hooks.decl_printable_name (current_function_decl, 2)); diff --git a/gcc/opts.c b/gcc/opts.c index 8699ec33703..e304ce5c94b 100644 --- a/gcc/opts.c +++ b/gcc/opts.c @@ -1062,6 +1062,11 @@ decode_options (unsigned int argc, const char **argv) "is disabled."); flag_toplevel_reorder = 0; } + + /* -Wmissing-noreturn is alias for -Wsuggest-attribute=noreturn. */ + if (warn_missing_noreturn) + warn_suggest_attribute_noreturn = true; + /* Unless the user has asked for section anchors, we disable toplevel reordering at -O0 to disable transformations that might be surprising to end users and to get -fno-toplevel-reorder tested. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e7eae084491..372d59518ea 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2010-06-11 Jan Hubicka <jh@suse.cz> + + * testsuite/gcc.dg/noreturn-7.c: Update. + * testsuite/gcc.dg/noreturn-4.c: Update. + 2010-06-10 Dodji Seketeli <dodji@redhat.com> Fix MIPS bootstrap diff --git a/gcc/testsuite/gcc.dg/noreturn-4.c b/gcc/testsuite/gcc.dg/noreturn-4.c index bcc29dac69a..6fe144754d0 100644 --- a/gcc/testsuite/gcc.dg/noreturn-4.c +++ b/gcc/testsuite/gcc.dg/noreturn-4.c @@ -4,7 +4,7 @@ extern void exit (int) __attribute__ ((__noreturn__)); int -main (void) /* { dg-warning "function might be possible candidate for attribute 'noreturn'" "warn for main" } */ +main (void) /* { dg-warning "function might be candidate for attribute 'noreturn'" "warn for main" } */ { exit (0); } diff --git a/gcc/testsuite/gcc.dg/noreturn-7.c b/gcc/testsuite/gcc.dg/noreturn-7.c index 1913be1fe1d..fd2be2d56c0 100644 --- a/gcc/testsuite/gcc.dg/noreturn-7.c +++ b/gcc/testsuite/gcc.dg/noreturn-7.c @@ -13,7 +13,7 @@ void _exit(int status) __attribute__ ((__noreturn__)); int z = 0; -void g() /* { dg-warning "possible candidate" } */ +void g() /* { dg-warning "might be candidate" } */ { if (++z > 10) _exit(0); @@ -27,14 +27,14 @@ void f() f(); } /* { dg-bogus "does return" } */ -int h() /* { dg-warning "possible candidate" } */ +int h() /* { dg-warning "might be candidate" } */ { if (++z > 10) _exit(0); return h(); } /* { dg-bogus "end of non-void function" } */ -int k() /* { dg-warning "possible candidate" } */ +int k() /* { dg-warning "might be candidate" } */ { if (++z > 10) _exit(0); diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c index f46556fe59a..406479416ae 100644 --- a/gcc/tree-cfg.c +++ b/gcc/tree-cfg.c @@ -7256,22 +7256,24 @@ struct gimple_opt_pass pass_warn_function_return = static unsigned int execute_warn_function_noreturn (void) { - if (warn_missing_noreturn - && !TREE_THIS_VOLATILE (cfun->decl) - && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0 - && !lang_hooks.missing_noreturn_ok_p (cfun->decl)) - warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn, - "function might be possible candidate " - "for attribute %<noreturn%>"); + if (!TREE_THIS_VOLATILE (current_function_decl) + && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0) + warn_function_noreturn (current_function_decl); return 0; } +static bool +gate_warn_function_noreturn (void) +{ + return warn_suggest_attribute_noreturn; +} + struct gimple_opt_pass pass_warn_function_noreturn = { { GIMPLE_PASS, "*warn_function_noreturn", /* name */ - NULL, /* gate */ + gate_warn_function_noreturn, /* gate */ execute_warn_function_noreturn, /* execute */ NULL, /* sub */ NULL, /* next */ diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c index fc2141f48c1..8dec8c76431 100644 --- a/gcc/tree-cfgcleanup.c +++ b/gcc/tree-cfgcleanup.c @@ -568,9 +568,23 @@ fixup_noreturn_call (gimple stmt) imm_use_iterator iter; gimple use_stmt; + /* All statements using the OP are unreachable or PHI + statements where the edge correspoing to OP use is unreachable. + We need to remove all normal statements so fixup_cfg will not + try to update them and keep all PHIs but remove use of the SSA + name or verifier will complain. */ FOR_EACH_IMM_USE_STMT (use_stmt, iter, op) - FOR_EACH_IMM_USE_ON_STMT (use_p, iter) - SET_USE (use_p, error_mark_node); + { + if (gimple_code (use_stmt) == GIMPLE_PHI) + FOR_EACH_IMM_USE_ON_STMT (use_p, iter) + SET_USE (use_p, error_mark_node); + else + { + gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt); + gsi_remove (&gsi, true); + } + } + release_ssa_name (op); } update_stmt (stmt); changed = true; diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h index f28ef31c2a9..1830ffa874e 100644 --- a/gcc/tree-flow.h +++ b/gcc/tree-flow.h @@ -872,6 +872,9 @@ unsigned int execute_free_datastructures (void); unsigned int execute_fixup_cfg (void); bool fixup_noreturn_call (gimple stmt); +/* In ipa-pure-const.c */ +void warn_function_noreturn (tree); + #include "tree-flow-inline.h" void swap_tree_operands (gimple, tree *, tree *); |