[C++ PATCH] Aligned new option handling fixes (PR c++/77651)
Jason Merrill
jason@redhat.com
Wed Sep 21 15:10:00 GMT 2016
OK.
On Wed, Sep 21, 2016 at 10:46 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> Hi!
>
> The following patch fixes some ICEs which were because of missing
> RejectNegative for the *aligned-new= options - they have their "negative"
> values as the option argument, so the only options that should allow
> negative forms are -Wno-aligned-new and -fno-aligned-new, not
> -Wno-aligned-new=none or -fno-aligned-new=32.
>
> Another thing is that sometimes the -Waligned-new warning suggests to use
> -faligned-new even when it is already on, that looks just too weird (it can
> be e.g. because some class has custom operator new defined in it, but not with
> std::align_val_t argument).
>
> Plus, I believe aligned_new_threshhold is a spelling typo, too many h chars.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2016-09-21 Jakub Jelinek <jakub@redhat.com>
>
> PR c++/77651
> c-family/
> * c.opt (Waligned-new=): Add RejectNegative.
> (faligned-new=): Likewise. Spelling fix - change
> aligned_new_threshhold to aligned_new_threshold.
> * c-cppbuiltin.c (c_cpp_builtins): Change aligned_new_threshhold
> to aligned_new_threshold.
> cp/
> * init.c (build_new_1): Don't suggest to use -faligned-new if
> aligned_new_threshold is non-zero.
> (type_has_new_extended_alignment): Change aligned_new_threshhold
> to aligned_new_threshold.
> * call.c (second_parm_is_size_t, aligned_allocation_fn_p,
> aligned_deallocation_fn_p, build_op_delete_call): Likewise.
> * decl.c (cxx_init_decl_processing): Likewise.
> testsuite/
> * g++.dg/cpp1z/aligned-new6.C: New test.
>
> --- gcc/c-family/c.opt.jj 2016-09-21 08:54:14.000000000 +0200
> +++ gcc/c-family/c.opt 2016-09-21 10:52:01.468493875 +0200
> @@ -288,7 +288,7 @@ C++ ObjC++ Alias(Waligned-new=,global,no
> Warn about 'new' of type with extended alignment without -faligned-new.
>
> Waligned-new=
> -C++ ObjC++ Var(warn_aligned_new) Enum(warn_aligned_new_level) Joined Warning LangEnabledBy(C++ ObjC++,Wall,1,0)
> +C++ ObjC++ Var(warn_aligned_new) Enum(warn_aligned_new_level) Joined RejectNegative Warning LangEnabledBy(C++ ObjC++,Wall,1,0)
> -Waligned-new=all Warn even if 'new' uses a class member allocation function.
>
> Wall
> @@ -1071,7 +1071,7 @@ C++ ObjC++ Alias(faligned-new=,1,0)
> Support C++17 allocation of over-aligned types.
>
> faligned-new=
> -C++ ObjC++ Joined Var(aligned_new_threshhold) UInteger Init(-1)
> +C++ ObjC++ Joined RejectNegative Var(aligned_new_threshold) UInteger Init(-1)
> -faligned-new=<N> Use C++17 over-aligned type allocation for alignments greater than N.
>
> fall-virtual
> --- gcc/c-family/c-cppbuiltin.c.jj 2016-09-13 10:43:54.000000000 +0200
> +++ gcc/c-family/c-cppbuiltin.c 2016-09-21 10:52:20.101258415 +0200
> @@ -944,11 +944,11 @@ c_cpp_builtins (cpp_reader *pfile)
> cpp_define (pfile, "__cpp_transactional_memory=210500");
> if (flag_sized_deallocation)
> cpp_define (pfile, "__cpp_sized_deallocation=201309");
> - if (aligned_new_threshhold)
> + if (aligned_new_threshold)
> {
> cpp_define (pfile, "__cpp_aligned_new=201606");
> cpp_define_formatted (pfile, "__STDCPP_DEFAULT_NEW_ALIGNMENT__=%d",
> - aligned_new_threshhold);
> + aligned_new_threshold);
> }
> }
> /* Note that we define this for C as well, so that we know if
> --- gcc/cp/init.c.jj 2016-09-14 23:49:03.000000000 +0200
> +++ gcc/cp/init.c 2016-09-21 11:06:57.953163363 +0200
> @@ -2574,8 +2574,8 @@ warn_placement_new_too_small (tree type,
> bool
> type_has_new_extended_alignment (tree t)
> {
> - return (aligned_new_threshhold
> - && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshhold);
> + return (aligned_new_threshold
> + && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshold);
> }
>
> /* Generate code for a new-expression, including calling the "operator
> @@ -3026,8 +3026,9 @@ build_new_1 (vec<tree, va_gc> **placemen
> "alignment %d", elt_type, TYPE_ALIGN_UNIT (elt_type));
> inform (input_location, "uses %qD, which does not have an alignment "
> "parameter", alloc_fn);
> - inform (input_location, "use %<-faligned-new%> to enable C++17 "
> - "over-aligned new support");
> + if (!aligned_new_threshold)
> + inform (input_location, "use %<-faligned-new%> to enable C++17 "
> + "over-aligned new support");
> }
>
> /* If we found a simple case of PLACEMENT_EXPR above, then copy it
> --- gcc/cp/call.c.jj 2016-09-13 10:43:56.000000000 +0200
> +++ gcc/cp/call.c 2016-09-21 10:53:07.607658081 +0200
> @@ -5965,7 +5965,7 @@ second_parm_is_size_t (tree fn)
> t = TREE_CHAIN (t);
> if (t == void_list_node)
> return true;
> - if (aligned_new_threshhold && t
> + if (aligned_new_threshold && t
> && same_type_p (TREE_VALUE (t), align_type_node)
> && TREE_CHAIN (t) == void_list_node)
> return true;
> @@ -5978,7 +5978,7 @@ second_parm_is_size_t (tree fn)
> bool
> aligned_allocation_fn_p (tree t)
> {
> - if (!aligned_new_threshhold)
> + if (!aligned_new_threshold)
> return false;
>
> tree a = FUNCTION_ARG_CHAIN (t);
> @@ -5992,7 +5992,7 @@ aligned_allocation_fn_p (tree t)
> static bool
> aligned_deallocation_fn_p (tree t)
> {
> - if (!aligned_new_threshhold)
> + if (!aligned_new_threshold)
> return false;
>
> /* A template instance is never a usual deallocation function,
> @@ -6202,7 +6202,7 @@ build_op_delete_call (enum tree_code cod
> selection process terminates. If more than one preferred
> function is found, all non-preferred functions are eliminated
> from further consideration. */
> - if (aligned_new_threshhold)
> + if (aligned_new_threshold)
> {
> bool want_align = type_has_new_extended_alignment (type);
> bool fn_align = aligned_deallocation_fn_p (fn);
> --- gcc/cp/decl.c.jj 2016-09-16 22:19:39.000000000 +0200
> +++ gcc/cp/decl.c 2016-09-21 10:53:38.191271599 +0200
> @@ -4132,16 +4132,16 @@ cxx_init_decl_processing (void)
> /* Now, C++. */
> current_lang_name = lang_name_cplusplus;
>
> - if (aligned_new_threshhold > 1
> - && !pow2p_hwi (aligned_new_threshhold))
> + if (aligned_new_threshold > 1
> + && !pow2p_hwi (aligned_new_threshold))
> {
> - error ("-faligned-new=%d is not a power of two", aligned_new_threshhold);
> - aligned_new_threshhold = 1;
> + error ("-faligned-new=%d is not a power of two", aligned_new_threshold);
> + aligned_new_threshold = 1;
> }
> - if (aligned_new_threshhold == -1)
> - aligned_new_threshhold = (cxx_dialect >= cxx1z) ? 1 : 0;
> - if (aligned_new_threshhold == 1)
> - aligned_new_threshhold = max_align_t_align () / BITS_PER_UNIT;
> + if (aligned_new_threshold == -1)
> + aligned_new_threshold = (cxx_dialect >= cxx1z) ? 1 : 0;
> + if (aligned_new_threshold == 1)
> + aligned_new_threshold = max_align_t_align () / BITS_PER_UNIT;
>
> {
> tree newattrs, extvisattr;
> @@ -4210,7 +4210,7 @@ cxx_init_decl_processing (void)
> push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
> }
>
> - if (aligned_new_threshhold)
> + if (aligned_new_threshold)
> {
> push_namespace (std_identifier);
> tree align_id = get_identifier ("align_val_t");
> --- gcc/testsuite/g++.dg/cpp1z/aligned-new6.C.jj 2016-09-21 10:43:40.773798919 +0200
> +++ gcc/testsuite/g++.dg/cpp1z/aligned-new6.C 2016-09-21 10:45:55.319109667 +0200
> @@ -0,0 +1,14 @@
> +// PR c++/77651
> +// { dg-do run { target { c++11 && c++14_down } } }
> +// { dg-options "-faligned-new -W -Wall -Wno-aligned-new" }
> +
> +struct alignas(64) A { int i; };
> +
> +int
> +main ()
> +{
> + A *p = new A;
> + if (((__UINTPTR_TYPE__) p) % 64 != 0)
> + __builtin_abort ();
> + delete p;
> +}
>
> Jakub
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