From e71585ffe2e1394858f0fcf809e86f1b324fe4e6 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Wed, 21 Nov 2018 11:55:11 +0000 Subject: Use gdb:array_view in call_function_by_hand & friends This replaces a few uses of pointer+length with gdb::array_view, in call_function_by_hand and related code. Unfortunately, due to -Wnarrowing, there are places where we can't brace-initialize an gdb::array_view without an ugly-ish cast. To avoid the cast, this patch introduces a gdb::make_array_view function. Unit tests included. This patch in isolation may not look so interesting, due to gdb::make_array_view uses, but I think it's still worth it. Some of the gdb::make_array_view calls disappear down the series, and others could be eliminated with more (non-trivial) gdb::array_view detangling/conversion (e.g. code around eval_call). See this as a "we have to start somewhere" patch. gdb/ChangeLog: 2018-11-21 Pedro Alves * ada-lang.c (ada_evaluate_subexp): Adjust to pass an array_view. * common/array-view.h (make_array_view): New. * compile/compile-object-run.c (compile_object_run): Adjust to pass an array_view. * elfread.c (elf_gnu_ifunc_resolve_addr): Adjust. * eval.c (eval_call): Adjust to pass an array_view. (evaluate_subexp_standard): Adjust to pass an array_view. * gcore.c (call_target_sbrk): Adjust to pass an array_view. * guile/scm-value.c (gdbscm_value_call): Likewise. * infcall.c (push_dummy_code): Replace pointer + size parameters with an array_view parameter. (call_function_by_hand, call_function_by_hand_dummy): Likewise and adjust. * infcall.h: Include "common/array-view.h". (call_function_by_hand, call_function_by_hand_dummy): Replace pointer + size parameters with an array_view parameter. * linux-fork.c (inferior_call_waitpid): Adjust to use array_view. * linux-tdep.c (linux_infcall_mmap): Likewise. * objc-lang.c (lookup_objc_class, lookup_child_selector) (value_nsstring, print_object_command): Likewise. * python/py-value.c (valpy_call): Likewise. * rust-lang.c (rust_evaluate_funcall): Likewise. * spu-tdep.c (flush_ea_cache): Likewise. * valarith.c (value_x_binop, value_x_unop): Likewise. * valops.c (value_allocate_space_in_inferior): Likewise. * unittests/array-view-selftests.c (run_tests): Add gdb::make_array_view test. --- gdb/common/array-view.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'gdb/common/array-view.h') diff --git a/gdb/common/array-view.h b/gdb/common/array-view.h index 319ea99..9c5fa2a 100644 --- a/gdb/common/array-view.h +++ b/gdb/common/array-view.h @@ -201,6 +201,48 @@ operator!= (const gdb::array_view &lhs, const gdb::array_view &rhs) return !(lhs == rhs); } +/* Create an array view from a pointer to an array and an element + count. + + This is useful as alternative to constructing an array_view using + brace initialization when the size variable you have handy is of + signed type, since otherwise without an explicit cast the code + would be ill-formed. + + For example, with: + + extern void foo (int, int, gdb::array_view); + + value *args[2]; + int nargs; + foo (1, 2, {values, nargs}); + + You'd get: + + source.c:10: error: narrowing conversion of ‘nargs’ from ‘int’ to + ‘size_t {aka long unsigned int}’ inside { } [-Werror=narrowing] + + You could fix it by writing the somewhat distracting explicit cast: + + foo (1, 2, {values, (size_t) nargs}); + + Or by instantiating an array_view explicitly: + + foo (1, 2, gdb::array_view(values, nargs)); + + Or, better, using make_array_view, which has the advantage of + inferring the arrav_view element's type: + + foo (1, 2, gdb::make_array_view (values, nargs)); +*/ + +template +constexpr inline array_view +make_array_view (U *array, size_t size) noexcept +{ + return {array, size}; +} + } /* namespace gdb */ #endif -- cgit v1.1