On Thu, 30 Nov 2023, Jason Merrill wrote:
> Tested x86_64-pc-linux-gnu, applying to trunk.
>
> -- 8< --
>
> In review of the deducing 'this' patch it came up that LAMBDA_EXPR_MUTABLE_P
> doesn't make sense for a lambda with an explicit object parameter. And it
> was never necessary, so let's remove it.
>
> gcc/cp/ChangeLog:
>
> * cp-tree.h (LAMBDA_EXPR_MUTABLE_P): Remove.
> * cp-tree.def: Remove documentation.
> * lambda.cc (build_lambda_expr): Remove reference.
> * parser.cc (cp_parser_lambda_declarator_opt): Likewise.
> * pt.cc (tsubst_lambda_expr): Likewise.
> * ptree.cc (cxx_print_lambda_node): Likewise.
> * semantics.cc (capture_decltype): Get the object quals
> from the object instead.
> ---
> gcc/cp/cp-tree.h | 5 -----
> gcc/cp/lambda.cc | 1 -
> gcc/cp/parser.cc | 1 -
> gcc/cp/pt.cc | 1 -
> gcc/cp/ptree.cc | 2 --
> gcc/cp/semantics.cc | 9 ++++++---
> gcc/cp/cp-tree.def | 3 +--
> 7 files changed, 7 insertions(+), 15 deletions(-)
>
> diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
> index 5614b71eed4..964af1ddd85 100644
> --- a/gcc/cp/cp-tree.h
> +++ b/gcc/cp/cp-tree.h
> @@ -461,7 +461,6 @@ extern GTY(()) tree cp_global_trees[CPTI_MAX];
> TYPENAME_IS_CLASS_P (in TYPENAME_TYPE)
> STMT_IS_FULL_EXPR_P (in _STMT)
> TARGET_EXPR_LIST_INIT_P (in TARGET_EXPR)
> - LAMBDA_EXPR_MUTABLE_P (in LAMBDA_EXPR)
> DECL_FINAL_P (in FUNCTION_DECL)
> QUALIFIED_NAME_IS_TEMPLATE (in SCOPE_REF)
> CONSTRUCTOR_IS_DEPENDENT (in CONSTRUCTOR)
> @@ -1478,10 +1477,6 @@ enum cp_lambda_default_capture_mode_type {
> #define LAMBDA_EXPR_CAPTURES_THIS_P(NODE) \
> LAMBDA_EXPR_THIS_CAPTURE(NODE)
>
> -/* Predicate tracking whether the lambda was declared 'mutable'. */
> -#define LAMBDA_EXPR_MUTABLE_P(NODE) \
> - TREE_LANG_FLAG_1 (LAMBDA_EXPR_CHECK (NODE))
> -
> /* True iff uses of a const variable capture were optimized away. */
> #define LAMBDA_EXPR_CAPTURE_OPTIMIZED(NODE) \
> TREE_LANG_FLAG_2 (LAMBDA_EXPR_CHECK (NODE))
> diff --git a/gcc/cp/lambda.cc b/gcc/cp/lambda.cc
> index 34d0190a89b..be8d240944d 100644
> --- a/gcc/cp/lambda.cc
> +++ b/gcc/cp/lambda.cc
> @@ -44,7 +44,6 @@ build_lambda_expr (void)
> LAMBDA_EXPR_THIS_CAPTURE (lambda) = NULL_TREE;
> LAMBDA_EXPR_REGEN_INFO (lambda) = NULL_TREE;
> LAMBDA_EXPR_PENDING_PROXIES (lambda) = NULL;
> - LAMBDA_EXPR_MUTABLE_P (lambda) = false;
> return lambda;
> }
>
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index 2464d1a0783..1826b6175f5 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -11770,7 +11770,6 @@ cp_parser_lambda_declarator_opt (cp_parser* parser,
> tree lambda_expr)
>
> if (lambda_specs.storage_class == sc_mutable)
> {
> - LAMBDA_EXPR_MUTABLE_P (lambda_expr) = 1;
> quals = TYPE_UNQUALIFIED;
> }
> else if (lambda_specs.storage_class == sc_static)
> diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
> index c18718b319d..00a808bf323 100644
> --- a/gcc/cp/pt.cc
> +++ b/gcc/cp/pt.cc
> @@ -19341,7 +19341,6 @@ tsubst_lambda_expr (tree t, tree args, tsubst_flags_t
> complain, tree in_decl)
> = LAMBDA_EXPR_LOCATION (t);
> LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
> = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
> - LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
> if (tree ti = LAMBDA_EXPR_REGEN_INFO (t))
> LAMBDA_EXPR_REGEN_INFO (r)
> = build_template_info (t, add_to_template_args (TI_ARGS (ti),
> diff --git a/gcc/cp/ptree.cc b/gcc/cp/ptree.cc
> index 32c5b5280dc..d1f58921fab 100644
> --- a/gcc/cp/ptree.cc
> +++ b/gcc/cp/ptree.cc
> @@ -265,8 +265,6 @@ cxx_print_identifier (FILE *file, tree node, int indent)
> void
> cxx_print_lambda_node (FILE *file, tree node, int indent)
> {
> - if (LAMBDA_EXPR_MUTABLE_P (node))
> - fprintf (file, " /mutable");
> fprintf (file, " default_capture_mode=[");
> switch (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (node))
> {
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index 04b0540599a..36b57ac9524 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -12792,9 +12792,12 @@ capture_decltype (tree decl)
>
> if (!TYPE_REF_P (type))
> {
> - if (!LAMBDA_EXPR_MUTABLE_P (lam))
> - type = cp_build_qualified_type (type, (cp_type_quals (type)
> - |TYPE_QUAL_CONST));
> + int quals = cp_type_quals (type);
> + tree obtype = TREE_TYPE (DECL_ARGUMENTS (current_function_decl));
> + gcc_checking_assert (!WILDCARD_TYPE_P (non_reference (obtype)));
> + if (INDIRECT_TYPE_P (obtype))
> + quals |= cp_type_quals (TREE_TYPE (obtype));
Shouldn't we propagate cv-quals of a by-value object parameter as well?
> + type = cp_build_qualified_type (type, quals);
> type = build_reference_type (type);
> }
> return type;
> diff --git a/gcc/cp/cp-tree.def b/gcc/cp/cp-tree.def
> index bf3bcd1bf13..fe47b0a10e6 100644
> --- a/gcc/cp/cp-tree.def
> +++ b/gcc/cp/cp-tree.def
> @@ -446,8 +446,7 @@ DEFTREECODE (TRAIT_TYPE, "trait_type", tcc_type, 0)
> LAMBDA_EXPR_CAPTURE_LIST holds the capture-list, including `this'.
> LAMBDA_EXPR_THIS_CAPTURE goes straight to the capture of `this', if it
> exists.
> LAMBDA_EXPR_PENDING_PROXIES is a vector of capture proxies which need to
> - be pushed once scope returns to the lambda.
> - LAMBDA_EXPR_MUTABLE_P signals whether this lambda was declared mutable.
> */
> + be pushed once scope returns to the lambda. */
> DEFTREECODE (LAMBDA_EXPR, "lambda_expr", tcc_exceptional, 0)
>
> /* The declared type of an expression. This is a C++0x extension.
>
> base-commit: fc7b70fa3497664a58b3c0b36fa94f9ec87d4f22
> --
> 2.39.3
>
>
