| Message ID | 20230505173648.1593931-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: goto entering scope of obj w/ non-trivial dtor [PR103091] | expand |
On 5/5/23 13:36, Patrick Palka wrote: > It seems DR 2256 permitted goto to cross the initialization of a > trivially initialized object with a non-trivial destructor. We > already supported this as an -fpermissive extension, so this patch > just makes us unconditionally support this. > > Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK > for trunk? OK. > DR 2256 > PR c++/103091 > > gcc/cp/ChangeLog: > > * decl.cc (decl_jump_unsafe): Return bool instead of int. > Don't consider TYPE_HAS_NONTRIVIAL_DESTRUCTOR. > (check_previous_goto_1): Simplify now that decl_jump_unsafe > returns bool instead of int. > (check_goto): Likewise. > > gcc/testsuite/ChangeLog: > > * g++.old-deja/g++.other/init9.C: Don't expect diagnostics for > goto made valid by DR 2256. > * g++.dg/init/goto4.C: New test. > --- > gcc/cp/decl.cc | 56 ++++++-------------- > gcc/testsuite/g++.dg/init/goto4.C | 22 ++++++++ > gcc/testsuite/g++.old-deja/g++.other/init9.C | 7 +-- > 3 files changed, 42 insertions(+), 43 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/init/goto4.C > > diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc > index 71d33d2b7a4..23a2b2fef0b 100644 > --- a/gcc/cp/decl.cc > +++ b/gcc/cp/decl.cc > @@ -69,7 +69,7 @@ enum bad_spec_place { > > static const char *redeclaration_error_message (tree, tree); > > -static int decl_jump_unsafe (tree); > +static bool decl_jump_unsafe (tree); > static void require_complete_types_for_parms (tree); > static tree grok_reference_init (tree, tree, tree, int); > static tree grokvardecl (tree, tree, tree, const cp_decl_specifier_seq *, > @@ -3548,10 +3548,9 @@ declare_local_label (tree id) > return ent ? ent->label_decl : NULL_TREE; > } > > -/* Returns nonzero if it is ill-formed to jump past the declaration of > - DECL. Returns 2 if it's also a real problem. */ > +/* Returns true if it is ill-formed to jump past the declaration of DECL. */ > > -static int > +static bool > decl_jump_unsafe (tree decl) > { > /* [stmt.dcl]/3: A program that jumps from a point where a local variable > @@ -3562,18 +3561,11 @@ decl_jump_unsafe (tree decl) > preceding types and is declared without an initializer (8.5). */ > tree type = TREE_TYPE (decl); > > - if (!VAR_P (decl) || TREE_STATIC (decl) > - || type == error_mark_node) > - return 0; > - > - if (DECL_NONTRIVIALLY_INITIALIZED_P (decl) > - || variably_modified_type_p (type, NULL_TREE)) > - return 2; > - > - if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) > - return 1; > - > - return 0; > + return (type != error_mark_node > + && VAR_P (decl) > + && !TREE_STATIC (decl) > + && (DECL_NONTRIVIALLY_INITIALIZED_P (decl) > + || variably_modified_type_p (type, NULL_TREE))); > } > > /* A subroutine of check_previous_goto_1 and check_goto to identify a branch > @@ -3625,27 +3617,18 @@ check_previous_goto_1 (tree decl, cp_binding_level* level, tree names, > new_decls = (DECL_P (new_decls) ? DECL_CHAIN (new_decls) > : TREE_CHAIN (new_decls))) > { > - int problem = decl_jump_unsafe (new_decls); > + bool problem = decl_jump_unsafe (new_decls); > if (! problem) > continue; > > if (!identified) > { > - complained = identify_goto (decl, input_location, locus, > - problem > 1 > - ? DK_ERROR : DK_PERMERROR); > + complained = identify_goto (decl, input_location, locus, DK_ERROR); > identified = 1; > } > if (complained) > - { > - if (problem > 1) > - inform (DECL_SOURCE_LOCATION (new_decls), > - " crosses initialization of %q#D", new_decls); > - else > - inform (DECL_SOURCE_LOCATION (new_decls), > - " enters scope of %q#D, which has " > - "non-trivial destructor", new_decls); > - } > + inform (DECL_SOURCE_LOCATION (new_decls), > + " crosses initialization of %q#D", new_decls); > } > > if (b == level) > @@ -3790,9 +3773,9 @@ check_goto (tree decl) > > FOR_EACH_VEC_SAFE_ELT (ent->bad_decls, ix, bad) > { > - int u = decl_jump_unsafe (bad); > + bool problem = decl_jump_unsafe (bad); > > - if (u > 1 && DECL_ARTIFICIAL (bad)) > + if (problem && DECL_ARTIFICIAL (bad)) > { > /* Can't skip init of __exception_info. */ > if (identified == 1) > @@ -3806,15 +3789,8 @@ check_goto (tree decl) > saw_catch = true; > } > else if (complained) > - { > - if (u > 1) > - inform (DECL_SOURCE_LOCATION (bad), > - " skips initialization of %q#D", bad); > - else > - inform (DECL_SOURCE_LOCATION (bad), > - " enters scope of %q#D which has " > - "non-trivial destructor", bad); > - } > + inform (DECL_SOURCE_LOCATION (bad), > + " skips initialization of %q#D", bad); > } > > if (complained) > diff --git a/gcc/testsuite/g++.dg/init/goto4.C b/gcc/testsuite/g++.dg/init/goto4.C > new file mode 100644 > index 00000000000..90ae52e6455 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/init/goto4.C > @@ -0,0 +1,22 @@ > +// DR 2256 > +// PR c++/103091 > +// { dg-do run } > + > +static int i; > + > +struct A { > + ~A() { ++i;} > +}; > + > +void f() { > + goto L; > + A a; > +L: > + return; > +} > + > +int main() { > + f(); > + if (i != 1) > + __builtin_abort(); > +} > diff --git a/gcc/testsuite/g++.old-deja/g++.other/init9.C b/gcc/testsuite/g++.old-deja/g++.other/init9.C > index 46d99028bdd..0194cd1b49a 100644 > --- a/gcc/testsuite/g++.old-deja/g++.other/init9.C > +++ b/gcc/testsuite/g++.old-deja/g++.other/init9.C > @@ -24,9 +24,10 @@ struct X { > }; > > void b() { > - goto bar; // { dg-message "" } jump from here > - X x; // { dg-message "" } jump crosses initialization > - bar: // { dg-error "" } jump to here > + // This was ill-formed until DR 2256. > + goto bar; > + X x; > + bar: > ; > } >
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 71d33d2b7a4..23a2b2fef0b 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -69,7 +69,7 @@ enum bad_spec_place { static const char *redeclaration_error_message (tree, tree); -static int decl_jump_unsafe (tree); +static bool decl_jump_unsafe (tree); static void require_complete_types_for_parms (tree); static tree grok_reference_init (tree, tree, tree, int); static tree grokvardecl (tree, tree, tree, const cp_decl_specifier_seq *, @@ -3548,10 +3548,9 @@ declare_local_label (tree id) return ent ? ent->label_decl : NULL_TREE; } -/* Returns nonzero if it is ill-formed to jump past the declaration of - DECL. Returns 2 if it's also a real problem. */ +/* Returns true if it is ill-formed to jump past the declaration of DECL. */ -static int +static bool decl_jump_unsafe (tree decl) { /* [stmt.dcl]/3: A program that jumps from a point where a local variable @@ -3562,18 +3561,11 @@ decl_jump_unsafe (tree decl) preceding types and is declared without an initializer (8.5). */ tree type = TREE_TYPE (decl); - if (!VAR_P (decl) || TREE_STATIC (decl) - || type == error_mark_node) - return 0; - - if (DECL_NONTRIVIALLY_INITIALIZED_P (decl) - || variably_modified_type_p (type, NULL_TREE)) - return 2; - - if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) - return 1; - - return 0; + return (type != error_mark_node + && VAR_P (decl) + && !TREE_STATIC (decl) + && (DECL_NONTRIVIALLY_INITIALIZED_P (decl) + || variably_modified_type_p (type, NULL_TREE))); } /* A subroutine of check_previous_goto_1 and check_goto to identify a branch @@ -3625,27 +3617,18 @@ check_previous_goto_1 (tree decl, cp_binding_level* level, tree names, new_decls = (DECL_P (new_decls) ? DECL_CHAIN (new_decls) : TREE_CHAIN (new_decls))) { - int problem = decl_jump_unsafe (new_decls); + bool problem = decl_jump_unsafe (new_decls); if (! problem) continue; if (!identified) { - complained = identify_goto (decl, input_location, locus, - problem > 1 - ? DK_ERROR : DK_PERMERROR); + complained = identify_goto (decl, input_location, locus, DK_ERROR); identified = 1; } if (complained) - { - if (problem > 1) - inform (DECL_SOURCE_LOCATION (new_decls), - " crosses initialization of %q#D", new_decls); - else - inform (DECL_SOURCE_LOCATION (new_decls), - " enters scope of %q#D, which has " - "non-trivial destructor", new_decls); - } + inform (DECL_SOURCE_LOCATION (new_decls), + " crosses initialization of %q#D", new_decls); } if (b == level) @@ -3790,9 +3773,9 @@ check_goto (tree decl) FOR_EACH_VEC_SAFE_ELT (ent->bad_decls, ix, bad) { - int u = decl_jump_unsafe (bad); + bool problem = decl_jump_unsafe (bad); - if (u > 1 && DECL_ARTIFICIAL (bad)) + if (problem && DECL_ARTIFICIAL (bad)) { /* Can't skip init of __exception_info. */ if (identified == 1) @@ -3806,15 +3789,8 @@ check_goto (tree decl) saw_catch = true; } else if (complained) - { - if (u > 1) - inform (DECL_SOURCE_LOCATION (bad), - " skips initialization of %q#D", bad); - else - inform (DECL_SOURCE_LOCATION (bad), - " enters scope of %q#D which has " - "non-trivial destructor", bad); - } + inform (DECL_SOURCE_LOCATION (bad), + " skips initialization of %q#D", bad); } if (complained) diff --git a/gcc/testsuite/g++.dg/init/goto4.C b/gcc/testsuite/g++.dg/init/goto4.C new file mode 100644 index 00000000000..90ae52e6455 --- /dev/null +++ b/gcc/testsuite/g++.dg/init/goto4.C @@ -0,0 +1,22 @@ +// DR 2256 +// PR c++/103091 +// { dg-do run } + +static int i; + +struct A { + ~A() { ++i;} +}; + +void f() { + goto L; + A a; +L: + return; +} + +int main() { + f(); + if (i != 1) + __builtin_abort(); +} diff --git a/gcc/testsuite/g++.old-deja/g++.other/init9.C b/gcc/testsuite/g++.old-deja/g++.other/init9.C index 46d99028bdd..0194cd1b49a 100644 --- a/gcc/testsuite/g++.old-deja/g++.other/init9.C +++ b/gcc/testsuite/g++.old-deja/g++.other/init9.C @@ -24,9 +24,10 @@ struct X { }; void b() { - goto bar; // { dg-message "" } jump from here - X x; // { dg-message "" } jump crosses initialization - bar: // { dg-error "" } jump to here + // This was ill-formed until DR 2256. + goto bar; + X x; + bar: ; }