For a span with statically empty extent, we currently model the
preconditions of front(), back(), and operator[] as if they are
mandates, by using a static_assert to verify that extent != 0. This
causes us to reject valid programs that would instantiate these member
functions and at runtime never call them.
Since they are already followed by more general runtime asserts, this
patch just removes these static_asserts altogether,
libstdc++-v3/ChangeLog:
* include/std/span (span::front): Remove static_assert.
(span::back): Likewise.
(span::operator[]): Likewise.
* testsuite/23_containers/span/back_neg.cc: Rewrite to verify
that we check the preconditions of back() only when it's called.
* testsuite/23_containers/span/front_neg.cc: Likewise for
front().
* testsuite/23_containers/span/index_op_neg.cc: Likewise for
operator[].
This fixes a division by zero in the selection-sampling std::__sample
overload when the input range is empty (and hence __unsampled_sz is 0).
libstdc++-v3/ChangeLog:
* include/bits/stl_algo.h (__sample): Exit early when the
input range is empty.
* testsuite/25_algorithms/sample/3.cc: New test.
As per P0202.
libstdc++-v3/ChangeLog:
* include/bits/stl_algo.h (for_each_n): Mark constexpr for C++20.
(search): Likewise for the overload that takes a searcher.
* testsuite/25_algorithms/for_each/constexpr.cc: Test constexpr
std::for_each_n.
* testsuite/25_algorithms/search/constexpr.cc: Test constexpr
std::search overload that takes a searcher.
Verify that arguments are pointers before calling handling code
that calls deref_rvalue on them.
gcc/analyzer/ChangeLog:
PR analyzer/97130
* region-model-impl-calls.cc (call_details::get_arg_type): New.
* region-model.cc (region_model::on_call_pre): Check that the
initial arg is a pointer before calling impl_call_memset and
impl_call_strlen.
* region-model.h (call_details::get_arg_type): New decl.
gcc/testsuite/ChangeLog:
PR analyzer/97130
* gcc.dg/analyzer/pr97130.c: New test.
Whilst debugging the remaining state explosion in PR analyzer/93355
I noticed that half of the states at an exploding program point had:
'malloc': {'&buf': 'non-heap'}
whereas the other half didn't, presumably depending on whether the path
to each enode had used this local buffer:
char buf[400];
This patch tweaks malloc_state_machine::get_default_state to be smarter
about this, so that we can implicitly treat pointers to decls as
non-heap, preventing pointless differences between sm_state_map
instances. With that, all of the states in question have equal (empty)
malloc sm-state - though the state explosion continues for other reasons.
gcc/analyzer/ChangeLog:
PR analyzer/93355
* sm-malloc.cc (malloc_state_machine::get_default_state): Look at
the base region when considering pointers. Treat pointers to
decls as being non-heap.
libstdc++-v3/ChangeLog:
* include/bits/c++config (__replacement_assert): Add noreturn
attribute.
(__glibcxx_assert_impl): Use __builtin_expect to hint that the
assertion is expected to pass.
libstdc++-v3/ChangeLog:
* include/std/ranges (drop_view::begin()): Adjust constraints
to match the correct condition for O(1) ranges::next (LWG 3482).
* testsuite/std/ranges/adaptors/drop.cc: Check that iterator is
cached for non-sized_range.
DR 1722 clarifies that the conversion function from lambda to pointer to
function should be noexcept(true).
gcc/cp/ChangeLog:
PR c++/90583
DR 1722
* lambda.c (maybe_add_lambda_conv_op): Mark the conversion function
as noexcept.
gcc/testsuite/ChangeLog:
PR c++/90583
DR 1722
* g++.dg/cpp0x/lambda/lambda-conv14.C: New test.
I noticed that clang++ has this CTAD warning and thought that it might
be useful to have it. From clang++: "Some style guides want to allow
using CTAD only on types that "opt-in"; i.e. on types that are designed
to support it and not just types that *happen* to work with it."
So this warning warns when CTAD deduced a type, but the type does not
define any deduction guides. In that case CTAD worked only because the
compiler synthesized the implicit deduction guides. That might not be
intended.
It can be suppressed by adding a deduction guide that will never be
considered:
struct allow_ctad_t;
template <typename T> struct S { S(T) {} };
S(allow_ctad_t) -> S<void>;
This warning is off by default. It doesn't warn when the type comes
from a system header unless -Wsystem-headers.
gcc/c-family/ChangeLog:
* c.opt (Wctad-maybe-unsupported): New option.
gcc/cp/ChangeLog:
* pt.c (deduction_guides_for): Add a bool parameter. Set it.
(do_class_deduction): Warn when CTAD succeeds but the type doesn't
have any explicit deduction guides.
gcc/ChangeLog:
* doc/invoke.texi: Document -Wctad-maybe-unsupported.
gcc/testsuite/ChangeLog:
* g++.dg/warn/Wctad-maybe-unsupported.C: New test.
* g++.dg/warn/Wctad-maybe-unsupported2.C: New test.
* g++.dg/warn/Wctad-maybe-unsupported3.C: New test.
* g++.dg/warn/Wctad-maybe-unsupported.h: New file.
Implement inline expansion of the intrinsic elemental subroutine MVBITS
with optional runtime checks for valid argument range.
gcc/fortran/ChangeLog:
* iresolve.c (gfc_resolve_mvbits): Remove unneeded conversion of
FROMPOS, LEN and TOPOS arguments to fit a C int.
* trans-intrinsic.c (gfc_conv_intrinsic_mvbits): Add inline
expansion of MVBITS intrinsic elemental subroutine and add code
for runtime argument checking.
(gfc_conv_intrinsic_subroutine): Recognise MVBITS intrinsic, but
defer handling to gfc_trans_call.
* trans-stmt.c (replace_ss):
(gfc_trans_call): Adjust to handle inline expansion, scalarization
of intrinsic subroutine MVBITS in gfc_conv_intrinsic_mvbits.
* trans.h (gfc_conv_intrinsic_mvbits): Add prototype for
gfc_conv_intrinsic_mvbits.
gcc/testsuite/ChangeLog:
* gfortran.dg/check_bits_2.f90: New test.
Co-authored-by: Paul Thomas <pault@gcc.gnu.org>
We don't need ts_lambda, as IDENTIFIER_LAMBDA_P is sufficient. Killed thusly.
gcc/cp/
* decl.c (xref_tag_1): Use IDENTIFIER_LAMBDA_P to detect lambdas.
* lambda.c (begin_lambda_type): Use ts_current to push the tag.
* name-lookup.h (enum tag_scope): Drop ts_lambda.
These testcases need thumb mode, which may not be the default.
Using dg-add-options arm_arch_v8_1m_main ensures that -mthumb is used
and makes the test pass in more configurations.
2020-09-21 Christophe Lyon <christophe.lyon@linaro.org>
gcc/testsuite/
* gcc.target/arm/csinc-1.c: Use dg-add-options
arm_arch_v8_1m_main.
* gcc.target/arm/csinv-1.c: Likewise.
* gcc.target/arm/csneg.c: Likewise.
This fixes SLP live lane extraction with pattern stmts.
2020-09-21 Richard Biener <rguenther@suse.de>
PR tree-optimization/97139
* tree-vect-slp.c (vect_bb_slp_mark_live_stmts): Only mark the
pattern root, track visited vectorized stmts.
* gcc.dg/vect/pr97139.c: New testcase.
[temp.deduct.guide]p3: Two deduction guide declarations in the same
translation unit for the same class template shall not have equivalent
parameter-declaration-clauses.
So let's detect that.
gcc/cp/ChangeLog:
PR c++/97099
* decl.c (redeclaration_error_message): Detect a redeclaration of
deduction guides.
gcc/testsuite/ChangeLog:
PR c++/97099
* g++.dg/cpp1z/class-deduction74.C: New test.
libstdc++-v3/ChangeLog:
* include/std/ranges (transform_view, elements_view): Relax
constraints on operator- for iterators, as per LWG 3483.
* testsuite/std/ranges/adaptors/elements.cc: Check that we
can take the difference of two iterators from a non-random
access range.
* testsuite/std/ranges/adaptors/transform.cc: Likewise.
The cast from void* to T* in std::assume_aligned is not valid in a
constexpr function. The optimization hint is redundant during constant
evaluation anyway (the compiler can see the object and knows its
alignment). Simply return the original pointer without applying the
__builtin_assume_aligned hint to it when doing constant evaluation.
This change also removes the preprocessor branch that works around
uintptr_t not being available. We already assume that type is present
elsewhere in the library.
libstdc++-v3/ChangeLog:
PR libstdc++/97132
* include/bits/align.h (align) [!_GLIBCXX_USE_C99_STDINT_TR1]:
Remove unused code.
(assume_aligned): Do not use __builtin_assume_aligned during
constant evaluation.
* testsuite/20_util/assume_aligned/1.cc: Improve test.
* testsuite/20_util/assume_aligned/97132.cc: New test.
2020-09-21 Jakub Jelinek <jakub@redhat.com>
* configure.ac: Use mallinfo mallinfo2 as first operand of
gcc_AC_CHECK_DECLS rather than [mallinfo, mallinfo2].
* configure: Regenerated.
* config.in: Regenerated.
2020-09-17 Andrea Corallo <andrea.corallo@arm.com>
* config/aarch64/aarch64-builtins.c
(aarch64_general_expand_builtin): Use expand machinery not to
alter the value of an rtx returned by force_reg.
The following fixes a dependence check where in the particular place
we cannot ignore self-dependences.
2020-09-21 Richard Biener <rguenther@suse.de>
PR tree-optimization/97135
* tree-ssa-loop-im.c (sm_seq_push_down): Do not ignore
self-dependences.
* gcc.dg/torture/pr97135.c: New testcase.
With SVE we can end up with:
switch (POLY_INT_CST [2, 2]) <default: <L2> [INV], case 2: <L3> [INV], case 4: <L3> [INV]>
which is fine to expand and we can remove the assert.
gcc/ChangeLog:
PR tree-optimization/96915
* tree-switch-conversion.c (switch_conversion::expand): Accept
also integer constants.
gcc/testsuite/ChangeLog:
PR tree-optimization/96915
* gcc.target/aarch64/sve/pr96915.c: New test.
gcc/ChangeLog
2020-09-14 Andrea Corallo <andrea.corallo@arm.com>
PR target/96968
* config/aarch64/aarch64-builtins.c
(aarch64_expand_fpsr_fpcr_setter): Fix comment nit.
(aarch64_expand_fpsr_fpcr_getter): New function, expand these
getters using expand_insn machinery.
(aarch64_general_expand_builtin): Make use of.
gcc/testsuite/ChangeLog
2020-09-14 Andrea Corallo <andrea.corallo@arm.com>
PR target/96968
* gcc.target/aarch64/pr96968.c: New test.
libstdc++-v3/ChangeLog:
PR libstdc++/97101
* include/std/functional (bind_front): Fix order of parameters
in is_nothrow_constructible_v specialization.
* testsuite/20_util/function_objects/bind_front/97101.cc: New test.
2020-09-20 John David Anglin < danglin@gcc.gnu.org>
gcc/ChangeLog
* config/pa/pa-hpux11.h (LINK_GCC_C_SEQUENCE_SPEC): Delete.
* config/pa/pa64-hpux.h (LINK_GCC_C_SEQUENCE_SPEC): Likewise.
(ENDFILE_SPEC): Link with libgcc_stub.a and mill.a.
* config/pa/pa32-linux.h (ENDFILE_SPEC): Link with libgcc.a.
gcc/ChangeLog:
PR c/50584
* attribs.c (decl_attributes): Also pass decl along with type
attributes to handlers.
(init_attr_rdwr_indices): Change second argument to attribute chain.
Handle internal attribute representation in addition to external.
(get_parm_access): New function.
(attr_access::to_internal_string): Define new member function.
(attr_access::to_external_string): Define new member function.
(attr_access::vla_bounds): Define new member function.
* attribs.h (struct attr_access): Declare new members.
(attr_access::from_mode_char): Define new member function.
(get_parm_access): Declare new function.
* calls.c (initialize_argument_information): Pass function type
attributes to init_attr_rdwr_indices.
* doc/invoke.texi (-Warray-parameter, -Wvla-parameter): Document.
* tree-pretty-print.c (dump_generic_node): Correct handling of
qualifiers.
* tree-ssa-uninit.c (maybe_warn_pass_by_reference): Same.
* tree.h (access_mode): Add new enumerator.
gcc/c-family/ChangeLog:
PR c/50584
* c-attribs.c (c_common_attribute_table): Add "arg spec" attribute.
(handle_argspec_attribute): New function.
(get_argument, get_argument_type): New functions.
(append_access_attrs): Add overload. Handle internal attribute
representation in addition to external.
(handle_access_attribute): Handle internal attribute representation
in addition to external.
(build_attr_access_from_parms): New function.
gcc/c-family/ChangeLog:
PR c/50584
* c-common.h (warn_parm_array_mismatch): Declare new function.
(has_attribute): Move declaration of an existing function.
(build_attr_access_from_parms): Declare new function.
* c-warn.c (parm_array_as_string): Define new function.
(plus_one): Define new function.
(warn_parm_ptrarray_mismatch): Define new function.
(warn_parm_array_mismatch): Define new function.
(vla_bound_parm_decl): New function.
* c.opt (-Warray-parameter, -Wvla-parameter): New options.
* c-pretty-print.c (pp_c_type_qualifier_list): Don't print array type
qualifiers here...
(c_pretty_printer::direct_abstract_declarator): ...but instead print
them in brackets here. Also print [static]. Strip extraneous
expressions from VLA bounds.
gcc/c/ChangeLog:
PR c/50584
* c-decl.c (lookup_last_decl): Define new function.
(c_decl_attributes): Call it.
(start_decl): Add argument and use it.
(finish_decl): Call build_attr_access_from_parms and decl_attributes.
(get_parm_array_spec): Define new function.
(push_parm_decl): Call get_parm_array_spec.
(start_function): Call warn_parm_array_mismatch. Build attribute
access and add it to current function.
* c-parser.c (c_parser_declaration_or_fndef): Diagnose mismatches
in forms of array parameters.
* c-tree.h (start_decl): Add argument.
gcc/testsuite/ChangeLog:
PR c/50584
* gcc.dg/attr-access-read-write-2.c: Adjust text of expected message.
* c-c++-common/Warray-bounds-6.c: Correct C++ declaration, adjust
text of expected diagnostics.
* gcc.dg/Wbuiltin-declaration-mismatch-9.c: Prune expected warning.
* gcc.dg/Warray-parameter-2.c: New test.
* gcc.dg/Warray-parameter-3.c: New test.
* gcc.dg/Warray-parameter-4.c: New test.
* gcc.dg/Warray-parameter-5.c: New test.
* gcc.dg/Warray-parameter.c: New test.
* gcc.dg/Wvla-parameter-2.c: New test.
* gcc.dg/Wvla-parameter-3.c: New test.
* gcc.dg/Wvla-parameter.c: New test.
2020-08-12 Sandra Loosemore <sandra@codesourcery.com>
gcc/c
* c-decl.c (c_break_label, c_cont_label): Delete, and replace
with...
(in_statement): New.
(start_function): Adjust for above change.
(c_push_function_context, c_pop_function_context): Likewise.
* c-lang.h (struct language_function): Likewise.
* c-objc-common.h (LANG_HOOKS_BLOCK_MAY_FALLTHRU): Define.
* c-parser.c (objc_foreach_break_label, objc_foreach_continue_label):
New.
(c_parser_statement_after_labels): Adjust calls to c_finish_bc_stmt.
(c_parser_switch_statement): Adjust break/switch context handling
and calls to renamed functions.
(c_parser_while_statement): Adjust break/switch context handling and
build a WHILE_STMT.
(c_parser_do_statement): Ditto, with DO_STMT respectively.
(c_parser_for_statement): Ditto, with FOR_STMT respectively.
(c_parser_omp_for_loop): Adjust break/switch context handling.
* c-tree.h (c_break_label, c_cont_label): Delete.
(IN_SWITCH_STMT, IN_ITERATION_STMT): Define.
(IN_OMP_BLOCK, IN_OMP_FOR, IN_OBJC_FOREACH): Define.
(in_statement, switch_statement_break_seen_p): Declare.
(c_start_case, c_finish_case): Renamed to...
(c_start_switch, c_finish_switch).
(c_finish_bc_stmt): Adjust arguments.
* c-typeck.c (build_function_call_vec): Don't try to print
statements with %qE format.
(struct c_switch): Rename switch_expr field to switch_stmt.
Add break_stmt_seen_p field.
(c_start_case): Rename to c_start_switch. Build a SWITCH_STMT
instead of a SWITCH_EXPR. Update for changes to struct c_switch.
(do_case): Update for changes to struct c_switch.
(c_finish_case): Rename to c_finish_switch. Update for changes to
struct c_switch and change of representation from SWITCH_EXPR to
SWITCH_STMT.
(c_finish_loop): Delete.
(c_finish_bc_stmt): Update to reflect changes to break/continue
state representation. Build a BREAK_STMT or CONTINUE_STMT instead
of a GOTO_EXPR except for objc foreach loops.
gcc/objc
* objc-act.c (objc_start_method_definition): Update to reflect
changes to break/continue state bookkeeping in C front end.
gcc/testsuite/
* gcc.dg/gomp/block-7.c: Update expected error message wording.
Switching the C++ front end to lower loops the same was as the C front
end triggered this error when bootstrapping the Fortran front end:
/path/to/gcc/fortran/interface.c:3546:12: error: '*new_arg' may be used uninitialized [-Werror=maybe-uninitialized]
3546 | new_arg[i]->next = NULL;
| ~~~~~~~~~^
Work around this by adding an assertion, which seems appropriate for
documentation and good coding practices anyway.
2020-08-12 Sandra Loosemore <sandra@codesourcery.com>
gcc/fortran/
* interface.c (gfc_compare_actual_formal): Add assertion after
main processing loop to silence maybe-uninitialized error.
The C and C++ front ends used to use the same strategy of lowering
loops to gotos with the end test canonicalized to the bottom of the
loop. In 2014 the C++ front end was changed to emit LOOP_EXPRs
instead (commit 1a45860e7757ee054f6bf98bee4ebe5c661dfb90).
As part of the unification of the C and C++ loop handling, it's
desirable to use the same lowering strategy for both languages.
Applying the C++ strategy to C caused a number of regressions in C
optimization tests, related to flipping the sense of the COND_EXPR for
the exit test and changes in block ordering in the output code. Many
of these regressions just require updating regexps in the test cases
but a few appear to be genuine optimization failures. Since it
appears the optimizers handle the C code better than C++ code, let's
go back to using the C strategy for both languages. The rationale for
the 2014 C++ patch (support for constexpr evaluation) has been solved
in other ways meanwhile.
2020-08-12 Sandra Loosemore <sandra@codesourcery.com>
gcc/c-family/
* c-gimplify.c (genericize_c_loop): Rewrite to match
c_finish_loop in c-typeck.c.
This patch moves the definitions for DO_STMT, FOR_STMT, WHILE_STMT,
SWITCH_STMT, BREAK_STMT, and CONTINUE_STMT from the C++ front end to
c-family. This includes the genericizers, pretty-printers, and dump
support as well as the tree definitions and accessors. Some related
code for OMP_FOR and similar OMP constructs is also moved.
2020-08-12 Sandra Loosemore <sandra@codesourcery.com>
gcc/c-family/
* c-common.c (c_block_may_fallthrough): New, split from
cxx_block_may_fallthrough in the cp front end.
(c_common_init_ts): Move handling of loop and switch-related
statements here from the cp front end.
* c-common.def (FOR_STMT, WHILE_STMT, DO_STMT): Move here from
cp front end.
(BREAK_STMT, CONTINUE_STMT, SWITCH_STMT): Likewise.
* c-common.h (c_block_may_fallthru): Declare.
(bc_state_t): Move here from cp front end.
(save_bc_state, restore_bc_state): Declare.
(c_genericize_control_stmt): Declare.
(WHILE_COND, WHILE_BODY): Likewise.
(DO_COND, DO_BODY): Likewise.
(FOR_INIT_STMT, FOR_COND, FOR_EXPR, FOR_BODY, FOR_SCOPE): Likewise.
(SWITCH_STMT_COND, SWITCH_STMT_BODY): Likewise.
(SWITCH_STMT_TYPE, SWITCH_STMT_SCOPE): Likewise.
(SWITCH_STMT_ALL_CASES_P, SWITCH_STMT_NO_BREAK_P): Likewise.
(LABEL_DECL_BREAK, LABEL_DECL_CONTINUE): Likewise.
* c-dump.c (dump_stmt): Copy from cp front end.
(c_dump_tree): Move code to handle structured loop and switch
tree nodes here from cp front end.
* c-gimplify.c: Adjust includes.
(enum bc_t, bc_label, begin_bc_block, finish_bc_block): Move from
cp front end.
(save_bc_state, restore_bc_state): New functions using old code
from cp front end.
(get_bc_label, expr_loc_or_loc): Move from cp front end.
(genericize_c_loop): Move from cp front end.
(genericize_for_stmt, genericize_while_stmt): Likewise.
(genericize_do_stmt, genericize_switch_stmt): Likewise.
(genericize_continue_stmt, genericize_break_stmt): Likewise.
(genericize_omp_for_stmt): Likewise.
(c_genericize_control_stmt): New function using code split from
cp front end.
(c_genericize_control_r): New.
(c_genericize): Call walk_tree with c_genericize_control_r.
* c-pretty-print.c (c_pretty_printer::statement): Move code to handle
structured loop and switch tree nodes here from cp front end.
gcc/cp/
* cp-gimplify.c (enum bc_t, bc_label): Move to c-family.
(begin_bc_block, finish_bc_block, get_bc_label): Likewise.
(genericize_cp_loop): Likewise.
(genericize_for_stmt, genericize_while_stmt): Likewise.
(genericize_do_stmt, genericize_switch_stmt): Likewise.
(genericize_continue_stmt, genericize_break_stmt): Likewise.
(genericize_omp_for_stmt): Likewise.
(cp_genericize_r): Call c_genericize_control_stmt instead of
above functions directly.
(cp_genericize): Call save_bc_state and restore_bc_state instead
of manipulating bc_label directly.
* cp-objcp-common.c (cxx_block_may_fallthru): Defer to
c_block_may_fallthru instead of handling SWITCH_STMT here.
(cp_common_init_ts): Move handling of loop and switch-related
statements to c-family.
* cp-tree.def (FOR_STMT, WHILE_STMT, DO_STMT): Move to c-family.
(BREAK_STMT, CONTINUE_STMT, SWITCH_STMT): Likewise.
* cp-tree.h (LABEL_DECL_BREAK, LABEL_DECL_CONTINUE): Likewise.
(WHILE_COND, WHILE_BODY): Likewise.
(DO_COND, DO_BODY): Likewise.
(FOR_INIT_STMT, FOR_COND, FOR_EXPR, FOR_BODY, FOR_SCOPE): Likewise.
(SWITCH_STMT_COND, SWITCH_STMT_BODY): Likewise.
(SWITCH_STMT_TYPE, SWITCH_STMT_SCOPE): Likewise.
(SWITCH_STMT_ALL_CASES_P, SWITCH_STMT_NO_BREAK_P): Likewise.
* cxx-pretty-print.c (cxx_pretty_printer::statement): Move code
to handle structured loop and switch tree nodes to c-family.
* dump.c (cp_dump_tree): Likewise.
gcc/
* doc/generic.texi (Basic Statements): Document SWITCH_EXPR here,
not SWITCH_STMT.
(Statements for C and C++): Rename node to reflect what
the introduction already says about sharing between C and C++
front ends. Copy-edit and correct documentation for structured
loops and switch.
Add a testcase to verify that -march=skylake-avx512 -mtune=skylake-avx512
generates desired code sequence.
PR target/96861
* gcc.target/i386/pr96861.c: New test.
