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2021-01-01Update copyright year range in all GDB filesJoel Brobecker1-1/+1
This commits the result of running gdb/copyright.py as per our Start of New Year procedure... gdb/ChangeLog Update copyright year range in copyright header of all GDB files.
2020-09-29Tweak gdbsupport/valid-expr.h for GCC 6, fix buildPedro Alves1-3/+5
With GCC 6.4 and 6.5 (at least), unit tests that use gdbsupport/valid-expr.h's CHECK_VALID fail to compile, with: In file included from src/gdb/unittests/offset-type-selftests.c:24:0: src/gdb/unittests/offset-type-selftests.c: In substitution of 'template<class Expected, template<class ...> class Op, class ... Args> using is_detected_exact = std::is_same<Expected, typename gdb::detection_detail::detector<gdb::nonesuch, void, Op, Args ...>::type> [with Expected = selftests::offset_type::off_A&; Op = selftests::offset_type::check_valid_expr75::archetype; Args = {selftests::offset_type::off_A, selftests::offset_type::off_B}]': src/gdb/unittests/offset-type-selftests.c:75:1: required from here src/gdb/../gdbsupport/valid-expr.h:65:20: error: type/value mismatch at argument 2 in template parameter list for 'template<class Expected, template<class ...> class Op, class ... Args> using is_detected_exact = std::is_same<Expected, typename gdb::detection_detail::detector<gdb::nonesuch, void, Op, Args ...>::type>' archetype, TYPES>::value == VALID, \ ^ The important part is the "error: type/value mismatch" error. Seems like that GCC doesn't understand that archetype is an alias template, and is being strict in requiring a template class. The fix here is then to make archetype a template class, to pacify GCC. The resulting code looks like this: template <TYPENAMES, typename = decltype (EXPR)> struct archetype { }; static_assert (gdb::is_detected_exact<archetype<TYPES, EXPR_TYPE>, archetype, TYPES>::value == VALID, ""); is_detected_exact<Expected, Op, Args> checks whether Op<Args> is type Expected: - For Expected, we pass the explicit EXPR_TYPE, overriding the default parameter type of archetype. - For Args we don't pass the last template parameter, so archtype defaults to the EXPR's decltype. So in essence, we're really checking whether EXPR_TYPE is the same as decltype(EXPR). We need to do the decltype in a template context in order to trigger SFINAE instead of failing to compile. The hunk in unittests/enum-flags-selftests.c becomes necessary, because unlike with the current alias template version, this new version makes GCC trigger -Wenum-compare warnings as well: src/gdb/unittests/enum-flags-selftests.c:328:33: error: comparison between 'enum selftests::enum_flags_tests::RE' and 'enum selftests::enum_flags_tests::RE2' [-Werror=enum-compare] CHECK_VALID (true, bool, RE () != RE2 ()) ^ src/gdb/../gdbsupport/valid-expr.h:61:45: note: in definition of macro 'CHECK_VALID_EXPR_INT' template <TYPENAMES, typename = decltype (EXPR)> \ ^ Build-tested with: - GCC {4.8.5, 6.4, 6.5, 7.3.1, 9.3.0, 11.0.0-20200910} - Clang 10.0.0 gdbsupport/ChangeLog: * valid-expr.h (CHECK_VALID_EXPR_INT): Make archetype a template class instead of an alias template and adjust static_assert. gdb/ChangeLog: * unittests/enum-flags-selftests.c: Check whether __GNUC__ is defined before using '#pragma GCC diagnostic' instead of checking __clang__.
2020-09-14Rewrite enum_flags, add unit tests, fix problemsPedro Alves1-0/+15
This patch started by adding comprehensive unit tests for enum_flags. For the testing part, it adds: - tests of normal expected uses of the API. - checks that _invalid_ uses of the API would fail to compile. I.e., it validates that enum_flags really is a strong type, and that incorrect mixing of enum types would be caught at compile time. It pulls that off making use of SFINEA and C++11's decltype/constexpr. This revealed many holes in the enum_flags API. For example, the f1 assignment below currently incorrectly fails to compile: enum_flags<flags> f1 = FLAG1; enum_flags<flags> f2 = FLAG2 | f1; The unit tests also revealed that this useful use case doesn't work: enum flag { FLAG1 = 1, FLAG2 = 2 }; enum_flags<flag> src = FLAG1; enum_flags<flag> f1 = condition ? src : FLAG2; It fails to compile because enum_flags<flag> and flag are convertible to each other. Turns out that making enum_flags be implicitly convertible to the backing raw enum type was not a good idea. If we make it convertible to the underlying type instead, we fix that ternary operator use case, and, we find cases throughout the codebase that should be using the enum_flags but were using the raw backing enum instead. So it's a good change overall. Also, several operators were missing. These holes and more are plugged by this patch, by reworking how the enum_flags operators are implemented, and making use of C++11's feature of being able to delete methods/functions. There are cases in gdb/compile/ where we need to call a function in a C plugin API that expects the raw enum. To address cases like that, this adds a "raw()" method to enum_flags. This way we can keep using the safer enum_flags to construct the value, and then be explicit when we need to get at the raw enum. This makes most of the enum_flags operators constexpr. Beyond enabling more compiler optimizations and enabling the new unit tests, this has other advantages, like making it possible to use operator| with enum_flags values in switch cases, where only compile-time constants are allowed: enum_flags<flags> f = FLAG1 | FLAG2; switch (f) { case FLAG1 | FLAG2: break; } Currently that fails to compile. It also switches to a different mechanism of enabling the global operators. The current mechanism isn't namespace friendly, the new one is. It also switches to C++11-style SFINAE -- instead of wrapping the return type in a SFINAE-friently structure, we use an unnamed template parameter. I.e., this: template <typename enum_type, typename = is_enum_flags_enum_type_t<enum_type>> enum_type operator& (enum_type e1, enum_type e2) instead of: template <typename enum_type> typename enum_flags_type<enum_type>::type operator& (enum_type e1, enum_type e2) Note that the static_assert inside operator~() was converted to a couple overloads (signed vs unsigned), because static_assert is too late for SFINAE-based tests, which is important for the CHECK_VALID unit tests. Tested with gcc {4.8, 7.1, 9.3} and clang {5.0.2, 10.0.0}. gdb/ChangeLog: * Makefile.in (SELFTESTS_SRCS): Add unittests/enum-flags-selftests.c. * btrace.c (ftrace_update_caller, ftrace_fixup_calle): Use btrace_function_flags instead of enum btrace_function_flag. * compile/compile-c-types.c (convert_qualified): Use enum_flags::raw. * compile/compile-cplus-symbols.c (convert_one_symbol) (convert_symbol_bmsym): * compile/compile-cplus-types.c (compile_cplus_convert_method) (compile_cplus_convert_struct_or_union_methods) (compile_cplus_instance::convert_qualified_base): * go-exp.y (parse_string_or_char): Add cast to int. * unittests/enum-flags-selftests.c: New file. * record-btrace.c (btrace_thread_flag_to_str): Change parameter's type to btrace_thread_flags from btrace_thread_flag. (record_btrace_cancel_resume, record_btrace_step_thread): Change local's type to btrace_thread_flags from btrace_thread_flag. Add cast in DEBUG call. gdbsupport/ChangeLog: * enum-flags.h: Include "traits.h". (DEF_ENUM_FLAGS_TYPE): Declare a function instead of defining a structure. (enum_underlying_type): Update comment. (namespace enum_flags_detail): New. Move struct zero_type here. (EnumIsUnsigned, EnumIsSigned): New. (class enum_flags): Make most methods constexpr. (operator&=, operator|=, operator^=): Take an enum_flags instead of an enum_type. Make rvalue ref versions deleted. (operator enum_type()): Delete. (operator&, operator|, operator^, operator~): Delete, moved out of class. (raw()): New method. (is_enum_flags_enum_type_t): Declare. (ENUM_FLAGS_GEN_BINOP, ENUM_FLAGS_GEN_COMPOUND_ASSIGN) (ENUM_FLAGS_GEN_COMP): New. Use them to reimplement global operators. (operator~): Now constexpr and reimplemented. (operator<<, operator>>): New deleted functions. * valid-expr.h (CHECK_VALID_EXPR_5, CHECK_VALID_EXPR_6): New.
2020-09-14Rewrite valid-expr.h's internals in terms of the detection idiom (C++17/N4502)Pedro Alves1-17/+3
An earlier attempt at doing this had failed (wouldn't work in GCCs around 4.8, IIRC), but now that I try again, it works. I suspect that my previous attempt did not use the pre C++14-safe void_t (in traits.h). I want to switch to this model because: - It's the standard detection idiom that folks will learn starting with C++17. - In the enum_flags unit tests, I have a static_assert that triggers a warning (resulting in build error), which GCC does not suppress because the warning is not being triggered in the SFINAE context. Switching to the detection idiom fixes that. Alternatively, switching to the C++03-style expression-validity checking with a varargs overload would allow addressing that, but I think that would be going backwards idiomatically speaking. - While this patch shows a net increase of lines of code, the magic being added to traits.h can be removed in a few years when we start requiring C++17. gdbsupport/ChangeLog: * traits.h (struct nonesuch, struct detector, detected_or) (detected_or_t, is_detected, detected_t, detected_or) (detected_or_t, is_detected_exact, is_detected_convertible): New. * valid-expr.h (CHECK_VALID_EXPR_INT): Use gdb::is_detected_exact.
2020-01-14Move gdbsupport to the top levelTom Tromey1-0/+108
This patch moves the gdbsupport directory to the top level. This is the next step in the ongoing project to move gdbserver to the top level. The bulk of this patch was created by "git mv gdb/gdbsupport gdbsupport". This patch then adds a build system to gdbsupport and wires it into the top level. Then it changes gdb to use the top-level build. gdbserver, on the other hand, is not yet changed. It still does its own build of gdbsupport. ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * src-release.sh (GDB_SUPPORT_DIRS): Add gdbsupport. * MAINTAINERS: Add gdbsupport. * configure: Rebuild. * configure.ac (configdirs): Add gdbsupport. * gdbsupport: New directory, move from gdb/gdbsupport. * Makefile.def (host_modules, dependencies): Add gnulib. * Makefile.in: Rebuild. gdb/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * nat/x86-linux-dregs.c: Include configh.h. * nat/linux-ptrace.c: Include configh.h. * nat/linux-btrace.c: Include configh.h. * defs.h: Include config.h, bfd.h. * configure.ac: Don't source common.host. (CONFIG_OBS, CONFIG_SRCS): Remove gdbsupport files. * configure: Rebuild. * acinclude.m4: Update path. * Makefile.in (SUPPORT, LIBSUPPORT, INCSUPPORT): New variables. (CONFIG_SRC_SUBDIR): Remove gdbsupport. (INTERNAL_CFLAGS_BASE): Add INCSUPPORT. (CLIBS): Add LIBSUPPORT. (CDEPS): Likewise. (COMMON_SFILES): Remove gdbsupport files. (HFILES_NO_SRCDIR): Likewise. (stamp-version): Update path to create-version.sh. (ALLDEPFILES): Remove gdbsupport files. gdb/gdbserver/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * server.h: Include config.h. * gdbreplay.c: Include config.h. * configure: Rebuild. * configure.ac: Don't source common.host. * acinclude.m4: Update path. * Makefile.in (INCSUPPORT): New variable. (INCLUDE_CFLAGS): Add INCSUPPORT. (SFILES): Update paths. (version-generated.c): Update path to create-version.sh. (gdbsupport/%-ipa.o, gdbsupport/%.o): Update paths. gdbsupport/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * common-defs.h: Add GDBSERVER case. Update includes. * acinclude.m4, aclocal.m4, config.in, configure, configure.ac, Makefile.am, Makefile.in, README: New files. * Moved from ../gdb/gdbsupport/ Change-Id: I07632e7798635c1bab389bf885971e584fb4bb78