Hi! On 2022-09-14T15:39:47+0200, Richard Biener via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > On Wed, Aug 24, 2022 at 2:13 PM <herron.phi...@googlemail.com> wrote: >> >> From: Philip Herron <philip.her...@embecosm.com> >> >> We have some rust specific langugage options note -fwrapv is enabled by >> default in the code. We are trying to respect options such as >> -Wunused-result which we get by porting over c++ no-discard for rust's >> must-use attribute, so we have enabled these by default directly here. > > LGTM
Actually, NACK. ;-) See <https://gcc.gnu.org/PR105914> "gccrs setting warn_unused_variable breaks thousands of non-Rust tests". The 'Init(1)' in 'gcc/rust/lang.opt' are in conflict with any (default) 'Init(0)' in other '*.opt' files -- remember that all '*.opt' files are processed together by GCC's "options machinery", and thus 'gcc/rust/lang.opt' may (and here, does) affect non-Rust front end code. I do have a patch series adding a 'LangInit(@var{language}, @var{value})' option property, and patches to use this in a lot of places (here and in other front ends' '*.opt' files), where currently we implement such logic in '*.cc' files; '[...]_init_options_struct' functions via 'LANG_HOOKS_INIT_OPTIONS_STRUCT' (those then largely become empty and may be removed). I assume this idea to be uncontroversial; I "just" need to get it polished and submitted... Grüße Thomas >> gcc/rust/lang.opt | 118 ++++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 118 insertions(+) >> create mode 100644 gcc/rust/lang.opt >> >> diff --git a/gcc/rust/lang.opt b/gcc/rust/lang.opt >> new file mode 100644 >> index 00000000000..1f6855ede1d >> --- /dev/null >> +++ b/gcc/rust/lang.opt >> @@ -0,0 +1,118 @@ >> +; Options for the Rust front end. >> +; Copyright (C) 2003-2022 Free Software Foundation, Inc. >> +; >> +; This file is part of GCC. >> +; >> +; GCC is free software; you can redistribute it and/or modify it under >> +; the terms of the GNU General Public License as published by the Free >> +; Software Foundation; either version 3, or (at your option) any later >> +; version. >> +; >> +; GCC is distributed in the hope that it will be useful, but WITHOUT ANY >> +; WARRANTY; without even the implied warranty of MERCHANTABILITY or >> +; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License >> +; for more details. >> +; >> +; You should have received a copy of the GNU General Public License >> +; along with GCC; see the file COPYING3. If not see >> +; <http://www.gnu.org/licenses/>. >> + >> +; See the GCC internals manual for a description of this file's format. >> + >> +; Please try to keep this file in ASCII collating order. >> + >> +; Describes command-line options used by this frontend >> + >> +Language >> +Rust >> + >> +I >> +Rust Joined Separate >> +; Documented in c.opt >> + >> +L >> +Rust Joined Separate >> +; Not documented >> + >> +Wall >> +Rust >> +; Documented in c.opt >> + >> +Wunused-variable >> +Rust Var(warn_unused_variable) Init(1) Warning >> +; documented in common.opt >> + >> +Wunused-const-variable >> +Rust Warning Alias(Wunused-const-variable=, 2, 0) >> +Warn when a const variable is unused. >> + >> +Wunused-const-variable= >> +Rust Joined RejectNegative UInteger Var(warn_unused_const_variable) Init(1) >> Warning LangEnabledBy(Rust,Wunused-variable, 1, 0) IntegerRange(0, 2) >> +Warn when a const variable is unused. >> + >> +Wunused-result >> +Rust Var(warn_unused_result) Init(1) Warning >> +Warn if a caller of a function, marked with attribute warn_unused_result, >> does not use its return value. >> + >> +frust-crate= >> +Rust Joined RejectNegative >> +-frust-crate=<name> Set the crate name for the compilation >> + >> +frust-debug >> +Rust Var(flag_rust_debug) >> +Dump various Rust front end internals. >> + >> +frust-dump- >> +Rust Joined RejectNegative >> +-frust-dump-<type> Dump Rust frontend internal information. >> + >> +frust-max-recursion-depth= >> +Rust RejectNegative Type(int) Var(rust_max_recursion_depth) Init(64) >> +-frust-max-recursion-depth=integer >> + >> +frust-mangling= >> +Rust Joined RejectNegative Enum(frust_mangling) Var(flag_rust_mangling) >> +-frust-mangling=[legacy|v0] Choose which version to use for name >> mangling >> + >> +Enum >> +Name(frust_mangling) Type(int) UnknownError(unknown rust mangling option >> %qs) >> + >> +EnumValue >> +Enum(frust_mangling) String(legacy) Value(0) >> + >> +EnumValue >> +Enum(frust_mangling) String(v0) Value(1) >> + >> +frust-cfg= >> +Rust Joined RejectNegative >> +-frust-cfg=<name> Set a config expansion option >> + >> +frust-edition= >> +Rust Joined RejectNegative Enum(frust_edition) Var(flag_rust_edition) >> +-frust-edition=[2015|2018|2021] Choose which edition to use >> when compiling rust code >> + >> +Enum >> +Name(frust_edition) Type(int) UnknownError(unknown rust edition %qs) >> + >> +EnumValue >> +Enum(frust_edition) String(2015) Value(0) >> + >> +EnumValue >> +Enum(frust_edition) String(2018) Value(1) >> + >> +EnumValue >> +Enum(frust_edition) String(2021) Value(2) >> + >> +frust-embed-metadata >> +Rust Var(flag_rust_embed_metadata) >> +Flag to enable embeding metadata directly into object files >> + >> +frust-metadata-output= >> +Rust Joined RejectNegative >> +-frust-metadata-output=<path.rox> Path to output crate metadata >> + >> +o >> +Rust Joined Separate >> +; Documented in common.opt >> + >> +; This comment is to ensure we retain the blank line above. >> -- >> 2.25.1 >> ----------------- Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201, 80634 München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht München, HRB 106955
