gccrs: Unify raw attribute values

Attribute values were used as raw string, this is error prone and
makes renaming harder. Using a constexpr instead will leverage the power
of the compiler and emit an error when an incorrect builtin attribute
value is used.

gcc/rust/ChangeLog:

	* ast/rust-ast.cc (Attribute::check_cfg_predicate): Change raw
	string to constexpr call.
	(Attribute::separate_cfg_attrs): Likewise.
	* backend/rust-compile-base.cc (should_mangle_item): Likewise.
	(HIRCompileBase::setup_fndecl): Likewise.
	(HIRCompileBase::handle_cold_attribute_on_fndecl): Likewise.
	* checks/errors/privacy/rust-privacy-reporter.cc (find_proc_macro_attribute):
	Likewise.
	* checks/errors/rust-unsafe-checker.cc (check_target_attr):
	Likewise.
	* expand/rust-cfg-strip.cc (fails_cfg): Likewise.
	(fails_cfg_with_expand): Likewise.
	(expand_cfg_attrs): Likewise.
	* expand/rust-macro-builtins.cc: Likewise.
	* hir/rust-ast-lower-base.cc (ASTLoweringBase::handle_outer_attributes): Likewise.
	(ASTLoweringBase::lower_macro_definition): Likewise.
	* hir/rust-hir-dump.cc (Dump::visit): Likewise.
	* parse/rust-parse-impl.h (Parser::parse_doc_comment): Likewise.
	* parse/rust-parse.cc (extract_module_path): Likewise.
	* resolve/rust-early-name-resolver.cc (is_macro_use_module):
	Likewise.
	(EarlyNameResolver::visit): Likewise.
	* resolve/rust-toplevel-name-resolver-2.0.cc (is_macro_export):
	Likwise.
	* rust-session-manager.cc (Session::injection): Likewise.
	* typecheck/rust-hir-type-check-base.cc (TypeCheckBase::parse_repr_options): Likewise.
	* util/rust-attributes.cc (is_proc_macro_type): Likewise.
	(AttributeChecker::check_attribute): Likewise.
	(AttributeChecker::visit): Likewise.
	* util/rust-hir-map.cc (Mappings::insert_macro_def): Likewise.
	* util/rust-attribute-values.h: New file.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/gcc/rust/util/rust-attribute-values.h b/gcc/rust/util/rust-attribute-values.h
new file mode 100644
index 0000000..513550a
--- /dev/null
+++ b/gcc/rust/util/rust-attribute-values.h
@@ -0,0 +1,40 @@
+#ifndef RUST_ATTRIBUTES_VALUE_H
+#define RUST_ATTRIBUTES_VALUE_H
+
+namespace Rust {
+namespace Values {
+// TODO: Change this to a namespace + inline constexpr in the future
+class Attributes
+{
+public:
+  static constexpr auto &INLINE = "inline";
+  static constexpr auto &COLD = "cold";
+  static constexpr auto &CFG = "cfg";
+  static constexpr auto &CFG_ATTR = "cfg_attr";
+  static constexpr auto &DEPRECATED = "deprecated";
+  static constexpr auto &ALLOW = "allow";
+  static constexpr auto &ALLOW_INTERNAL_UNSTABLE = "allow_internal_unstable";
+  static constexpr auto &DOC = "doc";
+  static constexpr auto &MUST_USE = "must_use";
+  static constexpr auto &LANG = "lang";
+  static constexpr auto &LINK_SECTION = "link_section";
+  static constexpr auto &NO_MANGLE = "no_mangle";
+  static constexpr auto &REPR = "repr";
+  static constexpr auto &RUSTC_BUILTIN_MACRO = "rustc_builtin_macro";
+  static constexpr auto &PATH = "path";
+  static constexpr auto &MACRO_USE = "macro_use";
+  static constexpr auto &MACRO_EXPORT = "macro_export";
+  static constexpr auto &PROC_MACRO = "proc_macro";
+  static constexpr auto &PROC_MACRO_DERIVE = "proc_macro_derive";
+  static constexpr auto &PROC_MACRO_ATTRIBUTE = "proc_macro_attribute";
+  static constexpr auto &TARGET_FEATURE = "target_feature";
+  // From now on, these are reserved by the compiler and gated through
+  // #![feature(rustc_attrs)]
+  static constexpr auto &RUSTC_INHERIT_OVERFLOW_CHECKS
+    = "rustc_inherit_overflow_checks";
+  static constexpr auto &STABLE = "stable";
+};
+} // namespace Values
+} // namespace Rust
+
+#endif /* !RUST_ATTRIBUTES_VALUE_H */