https://gcc.gnu.org/g:6d179035cd770d5b698cdd5d6a8c566d7c0b4b08
commit 6d179035cd770d5b698cdd5d6a8c566d7c0b4b08
Author: Pierre-Emmanuel Patry <pierre-emmanuel.pa...@embecosm.com>
Date: Wed Nov 22 15:15:29 2023 +0100
Make function bodies truly optional
Missing body on a function should be rejected at a later stage in the
compiler, not during parsing.
gcc/rust/ChangeLog:
* ast/rust-ast-collector.cc (TokenCollector::visit): Adapt defintion
getter.
* ast/rust-ast-visitor.cc (DefaultASTVisitor::visit): Likewise.
* expand/rust-cfg-strip.cc (CfgStrip::visit): Likewise.
* expand/rust-expand-visitor.cc (ExpandVisitor::visit): Likewise.
* hir/rust-ast-lower-implitem.h: Likewise.
* hir/rust-ast-lower-item.cc (ASTLoweringItem::visit): Likewise.
* resolve/rust-ast-resolve-item.cc (ResolveItem::visit): Likewise.
* resolve/rust-ast-resolve-stmt.h: Likewise.
* resolve/rust-default-resolver.cc (DefaultResolver::visit):
Likewise.
* util/rust-attributes.cc (AttributeChecker::visit): Likewise.
* parse/rust-parse-impl.h: Allow empty function body during parsing.
* ast/rust-ast.cc (Function::Function): Constructor now take an
optional for the body.
(Function::operator=): Adapt to new optional member.
(Function::as_string): Likewise.
* ast/rust-item.h (class Function): Make body optional and do not
rely on nullptr anymore.
Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.pa...@embecosm.com>
Diff:
---
gcc/rust/ast/rust-ast-collector.cc | 7 +-
gcc/rust/ast/rust-ast-visitor.cc | 3 +-
gcc/rust/ast/rust-ast.cc | 24 +++----
gcc/rust/ast/rust-item.h | 13 ++--
gcc/rust/expand/rust-cfg-strip.cc | 16 +++--
gcc/rust/expand/rust-expand-visitor.cc | 8 ++-
gcc/rust/hir/rust-ast-lower-implitem.h | 2 +-
gcc/rust/hir/rust-ast-lower-item.cc | 2 +-
gcc/rust/parse/rust-parse-impl.h | 105 +++++++++++++-----------------
gcc/rust/resolve/rust-ast-resolve-item.cc | 2 +-
gcc/rust/resolve/rust-ast-resolve-stmt.h | 2 +-
gcc/rust/resolve/rust-default-resolver.cc | 3 +-
gcc/rust/util/rust-attributes.cc | 3 +-
13 files changed, 92 insertions(+), 98 deletions(-)
diff --git a/gcc/rust/ast/rust-ast-collector.cc
b/gcc/rust/ast/rust-ast-collector.cc
index 647724bec11f..d5a98f1ccc78 100644
--- a/gcc/rust/ast/rust-ast-collector.cc
+++ b/gcc/rust/ast/rust-ast-collector.cc
@@ -1730,11 +1730,10 @@ TokenCollector::visit (Function &function)
if (function.has_where_clause ())
visit (function.get_where_clause ());
- auto &block = function.get_definition ();
- if (!block)
- push (Rust::Token::make (SEMICOLON, UNDEF_LOCATION));
+ if (function.has_body ())
+ visit (*function.get_definition ());
else
- visit (block);
+ push (Rust::Token::make (SEMICOLON, UNDEF_LOCATION));
newline ();
}
diff --git a/gcc/rust/ast/rust-ast-visitor.cc b/gcc/rust/ast/rust-ast-visitor.cc
index 4ec5c7cf1d0a..230a152b05bd 100644
--- a/gcc/rust/ast/rust-ast-visitor.cc
+++ b/gcc/rust/ast/rust-ast-visitor.cc
@@ -777,7 +777,8 @@ DefaultASTVisitor::visit (AST::Function &function)
if (function.has_return_type ())
visit (function.get_return_type ());
visit (function.get_where_clause ());
- visit (function.get_definition ());
+ if (function.has_body ())
+ visit (*function.get_definition ());
}
void
diff --git a/gcc/rust/ast/rust-ast.cc b/gcc/rust/ast/rust-ast.cc
index 15d7880bce45..88ac8608bb62 100644
--- a/gcc/rust/ast/rust-ast.cc
+++ b/gcc/rust/ast/rust-ast.cc
@@ -18,6 +18,7 @@ along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "rust-ast.h"
+#include "optional.h"
#include "rust-system.h"
#include "rust-ast-full.h"
#include "rust-diagnostics.h"
@@ -1100,8 +1101,10 @@ Function::Function (Function const &other)
return_type = other.return_type->clone_type ();
// guard to prevent null dereference (only required if error state)
- if (other.function_body != nullptr)
- function_body = other.function_body->clone_block_expr ();
+ if (other.has_body ())
+ function_body = other.function_body.value ()->clone_block_expr ();
+ else
+ function_body = tl::nullopt;
generic_params.reserve (other.generic_params.size ());
for (const auto &e : other.generic_params)
@@ -1131,10 +1134,10 @@ Function::operator= (Function const &other)
return_type = nullptr;
// guard to prevent null dereference (only required if error state)
- if (other.function_body != nullptr)
- function_body = other.function_body->clone_block_expr ();
+ if (other.has_body ())
+ function_body = other.function_body.value ()->clone_block_expr ();
else
- function_body = nullptr;
+ function_body = tl::nullopt;
generic_params.reserve (other.generic_params.size ());
for (const auto &e : other.generic_params)
@@ -1221,15 +1224,8 @@ Function::as_string () const
str += "\n";
- // DEBUG: null pointer check
- if (function_body == nullptr)
- {
- rust_debug (
- "something really terrible has gone wrong - null pointer function "
- "body in function.");
- return "NULL_POINTER_MARK";
- }
- str += function_body->as_string () + "\n";
+ if (has_body ())
+ str += function_body.value ()->as_string () + "\n";
return str;
}
diff --git a/gcc/rust/ast/rust-item.h b/gcc/rust/ast/rust-item.h
index bed8312497ac..685f9493370e 100644
--- a/gcc/rust/ast/rust-item.h
+++ b/gcc/rust/ast/rust-item.h
@@ -1299,7 +1299,7 @@ class Function : public VisItem,
std::vector<std::unique_ptr<Param>> function_params;
std::unique_ptr<Type> return_type;
WhereClause where_clause;
- std::unique_ptr<BlockExpr> function_body;
+ tl::optional<std::unique_ptr<BlockExpr>> function_body;
location_t locus;
bool is_default;
@@ -1323,14 +1323,16 @@ public:
return function_params.size () > 0 && function_params[0]->is_self ();
}
+ bool has_body () const { return function_body.has_value (); }
+
// Mega-constructor with all possible fields
Function (Identifier function_name, FunctionQualifiers qualifiers,
std::vector<std::unique_ptr<GenericParam>> generic_params,
std::vector<std::unique_ptr<Param>> function_params,
std::unique_ptr<Type> return_type, WhereClause where_clause,
- std::unique_ptr<BlockExpr> function_body, Visibility vis,
- std::vector<Attribute> outer_attrs, location_t locus,
- bool is_default = false)
+ tl::optional<std::unique_ptr<BlockExpr>> function_body,
+ Visibility vis, std::vector<Attribute> outer_attrs,
+ location_t locus, bool is_default = false)
: VisItem (std::move (vis), std::move (outer_attrs)),
qualifiers (std::move (qualifiers)),
function_name (std::move (function_name)),
@@ -1390,9 +1392,8 @@ public:
}
// TODO: is this better? Or is a "vis_block" better?
- std::unique_ptr<BlockExpr> &get_definition ()
+ tl::optional<std::unique_ptr<BlockExpr>> &get_definition ()
{
- rust_assert (function_body != nullptr);
return function_body;
}
diff --git a/gcc/rust/expand/rust-cfg-strip.cc
b/gcc/rust/expand/rust-cfg-strip.cc
index 7e50db6b1c57..36fe3a151264 100644
--- a/gcc/rust/expand/rust-cfg-strip.cc
+++ b/gcc/rust/expand/rust-cfg-strip.cc
@@ -2031,13 +2031,17 @@ CfgStrip::visit (AST::Function &function)
/* body should always exist - if error state, should have returned
* before now */
// can't strip block itself, but can strip sub-expressions
- auto &block_expr = function.get_definition ();
- block_expr->accept_vis (*this);
- if (block_expr->is_marked_for_strip ())
- rust_error_at (block_expr->get_locus (),
- "cannot strip block expression in this position - outer "
- "attributes not allowed");
+ if (function.has_body ())
+ {
+ auto &block_expr = function.get_definition ().value ();
+ block_expr->accept_vis (*this);
+ if (block_expr->is_marked_for_strip ())
+ rust_error_at (block_expr->get_locus (),
+ "cannot strip block expression in this position - outer "
+ "attributes not allowed");
+ }
}
+
void
CfgStrip::visit (AST::TypeAlias &type_alias)
{
diff --git a/gcc/rust/expand/rust-expand-visitor.cc
b/gcc/rust/expand/rust-expand-visitor.cc
index 1745af061746..ad473c2dcb0e 100644
--- a/gcc/rust/expand/rust-expand-visitor.cc
+++ b/gcc/rust/expand/rust-expand-visitor.cc
@@ -1001,8 +1001,9 @@ ExpandVisitor::visit (AST::UseDeclaration &use_decl)
void
ExpandVisitor::visit (AST::Function &function)
{
- visit_inner_using_attrs (function,
- function.get_definition ()->get_inner_attrs ());
+ if (function.has_body ())
+ visit_inner_using_attrs (
+ function, function.get_definition ().value ()->get_inner_attrs ());
for (auto ¶m : function.get_generic_params ())
visit (param);
@@ -1014,7 +1015,8 @@ ExpandVisitor::visit (AST::Function &function)
if (function.has_where_clause ())
expand_where_clause (function.get_where_clause ());
- visit (function.get_definition ());
+ if (function.has_body ())
+ visit (*function.get_definition ());
}
void
diff --git a/gcc/rust/hir/rust-ast-lower-implitem.h
b/gcc/rust/hir/rust-ast-lower-implitem.h
index 91602c9efbb1..249f9d88a6bb 100644
--- a/gcc/rust/hir/rust-ast-lower-implitem.h
+++ b/gcc/rust/hir/rust-ast-lower-implitem.h
@@ -168,7 +168,7 @@ public:
bool terminated = false;
std::unique_ptr<HIR::BlockExpr> function_body
= std::unique_ptr<HIR::BlockExpr> (
- ASTLoweringBlock::translate (function.get_definition ().get (),
+ ASTLoweringBlock::translate (function.get_definition ()->get (),
&terminated));
auto crate_num = mappings->get_current_crate ();
diff --git a/gcc/rust/hir/rust-ast-lower-item.cc
b/gcc/rust/hir/rust-ast-lower-item.cc
index c024acf60f98..01494ae028c8 100644
--- a/gcc/rust/hir/rust-ast-lower-item.cc
+++ b/gcc/rust/hir/rust-ast-lower-item.cc
@@ -446,7 +446,7 @@ ASTLoweringItem::visit (AST::Function &function)
bool terminated = false;
std::unique_ptr<HIR::BlockExpr> function_body
= std::unique_ptr<HIR::BlockExpr> (
- ASTLoweringBlock::translate (function.get_definition ().get (),
+ ASTLoweringBlock::translate (function.get_definition ()->get (),
&terminated));
auto crate_num = mappings->get_current_crate ();
diff --git a/gcc/rust/parse/rust-parse-impl.h b/gcc/rust/parse/rust-parse-impl.h
index b8c40c3c1577..12c34d98956f 100644
--- a/gcc/rust/parse/rust-parse-impl.h
+++ b/gcc/rust/parse/rust-parse-impl.h
@@ -23,6 +23,7 @@
* This is also the reason why there are no include guards. */
#include "rust-common.h"
+#include "rust-expr.h"
#include "rust-item.h"
#include "rust-common.h"
#include "rust-token.h"
@@ -2976,14 +2977,21 @@ Parser<ManagedTokenSource>::parse_function
(AST::Visibility vis,
// parse where clause - if exists
AST::WhereClause where_clause = parse_where_clause ();
- // parse block expression
- std::unique_ptr<AST::BlockExpr> block_expr = parse_block_expr ();
+ tl::optional<std::unique_ptr<AST::BlockExpr>> body = tl::nullopt;
+ if (lexer.peek_token ()->get_id () == SEMICOLON)
+ lexer.skip_token ();
+ else
+ {
+ std::unique_ptr<AST::BlockExpr> block_expr = parse_block_expr ();
+ if (block_expr != nullptr)
+ body = std::move (block_expr);
+ }
return std::unique_ptr<AST::Function> (
new AST::Function (std::move (function_name), std::move (qualifiers),
std::move (generic_params), std::move (function_params),
std::move (return_type), std::move (where_clause),
- std::move (block_expr), std::move (vis),
+ std::move (body), std::move (vis),
std::move (outer_attrs), locus));
}
@@ -5710,49 +5718,33 @@
Parser<ManagedTokenSource>::parse_inherent_impl_function_or_method (
// parse where clause (optional)
AST::WhereClause where_clause = parse_where_clause ();
- // parse function definition (in block) - semicolon not allowed
+ tl::optional<std::unique_ptr<AST::BlockExpr>> body = tl::nullopt;
if (lexer.peek_token ()->get_id () == SEMICOLON)
+ lexer.skip_token ();
+ else
{
- Error error (lexer.peek_token ()->get_locus (),
- "%s declaration in inherent impl not allowed - must have "
- "a definition",
- is_method ? "method" : "function");
- add_error (std::move (error));
+ auto result = parse_block_expr ();
- lexer.skip_token ();
- return nullptr;
- }
- std::unique_ptr<AST::BlockExpr> body = parse_block_expr ();
- if (body == nullptr)
- {
- Error error (lexer.peek_token ()->get_locus (),
- "could not parse definition in inherent impl %s definition",
- is_method ? "method" : "function");
- add_error (std::move (error));
+ if (result == nullptr)
+ {
+ Error error (
+ lexer.peek_token ()->get_locus (),
+ "could not parse definition in inherent impl %s definition",
+ is_method ? "method" : "function");
+ add_error (std::move (error));
- skip_after_end_block ();
- return nullptr;
+ skip_after_end_block ();
+ return nullptr;
+ }
+ body = std::move (result);
}
- // do actual if instead of ternary for return value optimisation
- if (is_method)
- {
- return std::unique_ptr<AST::Function> (
- new AST::Function (std::move (ident), std::move (qualifiers),
- std::move (generic_params),
- std::move (function_params), std::move (return_type),
- std::move (where_clause), std::move (body),
- std::move (vis), std::move (outer_attrs), locus));
- }
- else
- {
- return std::unique_ptr<AST::Function> (
- new AST::Function (std::move (ident), std::move (qualifiers),
- std::move (generic_params),
- std::move (function_params), std::move (return_type),
- std::move (where_clause), std::move (body),
- std::move (vis), std::move (outer_attrs), locus));
- }
+ return std::unique_ptr<AST::Function> (
+ new AST::Function (std::move (ident), std::move (qualifiers),
+ std::move (generic_params), std::move (function_params),
+ std::move (return_type), std::move (where_clause),
+ std::move (body), std::move (vis),
+ std::move (outer_attrs), locus));
}
// Parses a single trait impl item (item inside a trait impl block).
@@ -5960,27 +5952,24 @@
Parser<ManagedTokenSource>::parse_trait_impl_function_or_method (
"successfully parsed where clause in function or method trait impl item");
// parse function definition (in block) - semicolon not allowed
- if (lexer.peek_token ()->get_id () == SEMICOLON)
- {
- Error error (
- lexer.peek_token ()->get_locus (),
- "%s declaration in trait impl not allowed - must have a definition",
- is_method ? "method" : "function");
- add_error (std::move (error));
+ tl::optional<std::unique_ptr<AST::BlockExpr>> body = tl::nullopt;
- lexer.skip_token ();
- return nullptr;
- }
- std::unique_ptr<AST::BlockExpr> body = parse_block_expr ();
- if (body == nullptr)
+ if (lexer.peek_token ()->get_id () == SEMICOLON)
+ lexer.skip_token ();
+ else
{
- Error error (lexer.peek_token ()->get_locus (),
- "could not parse definition in trait impl %s definition",
- is_method ? "method" : "function");
- add_error (std::move (error));
+ auto result = parse_block_expr ();
+ if (result == nullptr)
+ {
+ Error error (lexer.peek_token ()->get_locus (),
+ "could not parse definition in trait impl %s definition",
+ is_method ? "method" : "function");
+ add_error (std::move (error));
- skip_after_end_block ();
- return nullptr;
+ skip_after_end_block ();
+ return nullptr;
+ }
+ body = std::move (result);
}
return std::unique_ptr<AST::Function> (
diff --git a/gcc/rust/resolve/rust-ast-resolve-item.cc
b/gcc/rust/resolve/rust-ast-resolve-item.cc
index 31565043522d..fc08098b433e 100644
--- a/gcc/rust/resolve/rust-ast-resolve-item.cc
+++ b/gcc/rust/resolve/rust-ast-resolve-item.cc
@@ -616,7 +616,7 @@ ResolveItem::visit (AST::Function &function)
}
// resolve the function body
- ResolveExpr::go (function.get_definition ().get (), path, cpath);
+ ResolveExpr::go (function.get_definition ()->get (), path, cpath);
resolver->get_name_scope ().pop ();
resolver->get_type_scope ().pop ();
diff --git a/gcc/rust/resolve/rust-ast-resolve-stmt.h
b/gcc/rust/resolve/rust-ast-resolve-stmt.h
index 3be5f128a15d..c1111a6159a2 100644
--- a/gcc/rust/resolve/rust-ast-resolve-stmt.h
+++ b/gcc/rust/resolve/rust-ast-resolve-stmt.h
@@ -378,7 +378,7 @@ public:
}
// resolve the function body
- ResolveExpr::go (function.get_definition ().get (), path, cpath);
+ ResolveExpr::go (function.get_definition ()->get (), path, cpath);
resolver->get_name_scope ().pop ();
resolver->get_type_scope ().pop ();
diff --git a/gcc/rust/resolve/rust-default-resolver.cc
b/gcc/rust/resolve/rust-default-resolver.cc
index 1ab174b6caa4..c1ed3cea1136 100644
--- a/gcc/rust/resolve/rust-default-resolver.cc
+++ b/gcc/rust/resolve/rust-default-resolver.cc
@@ -77,7 +77,8 @@ DefaultResolver::visit (AST::Function &function)
}
}
- function.get_definition ()->accept_vis (*this);
+ if (function.has_body ())
+ function.get_definition ().value ()->accept_vis (*this);
};
ctx.scoped (Rib::Kind::Function, function.get_node_id (), def_fn);
diff --git a/gcc/rust/util/rust-attributes.cc b/gcc/rust/util/rust-attributes.cc
index 5a43224f01c7..4975f10890f5 100644
--- a/gcc/rust/util/rust-attributes.cc
+++ b/gcc/rust/util/rust-attributes.cc
@@ -667,7 +667,8 @@ AttributeChecker::visit (AST::Function &fun)
else if (result.name == "no_mangle")
check_no_mangle_function (attribute, fun);
}
- fun.get_definition ()->accept_vis (*this);
+ if (fun.has_body ())
+ fun.get_definition ().value ()->accept_vis (*this);
}
void
