[PATCH] c++: Member initializer list diagnostic locations [PR94024]
Jason Merrill
jason@redhat.com
Mon Aug 3 20:10:29 GMT 2020
On 8/3/20 2:49 PM, Patrick Palka wrote:
> On Mon, 3 Aug 2020, Jason Merrill wrote:
>
>> On 8/3/20 10:14 AM, Patrick Palka wrote:
>>> This patch preserves the source locations of each node in a member
>>> initializer list so that during processing of the list we can set
>>> input_location appropriately for generally more accurate diagnostic
>>> locations. Since TREE_LIST nodes are tcc_exceptional, they can't have
>>> source locations, so we instead store the location in a dummy
>>> tcc_expression node within the TREE_TYPE of the list node.
>>
>>> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK to
>>> commit?
>>>
>>> gcc/cp/ChangeLog:
>>>
>>> PR c++/94024
>>> * init.c (sort_mem_initializers): Preserve TREE_TYPE of the
>>> member initializer list node.
>>> (emit_mem_initializers): Set input_location when performing each
>>> member initialization.
>>> * parser.c (cp_parser_mem_initializer_list): Attach the source
>>> location of this initializer to a dummy EMPTY_CLASS_EXPR within
>>> the TREE_TYPE of the list node.
>>> * pt.c (tsubst_initializer_list): Preserve TREE_TYPE of the
>>> member initializer list node.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> PR c++/94024
>>> * g++.dg/diagnostic/mem-init1.C: New test.
>>> ---
>>> gcc/cp/init.c | 6 +++++
>>> gcc/cp/parser.c | 8 ++++++
>>> gcc/cp/pt.c | 3 +++
>>> gcc/testsuite/g++.dg/diagnostic/mem-init1.C | 29 +++++++++++++++++++++
>>> 4 files changed, 46 insertions(+)
>>> create mode 100644 gcc/testsuite/g++.dg/diagnostic/mem-init1.C
>>>
>>> diff --git a/gcc/cp/init.c b/gcc/cp/init.c
>>> index cb9bd2dbfba..3f089404cf2 100644
>>> --- a/gcc/cp/init.c
>>> +++ b/gcc/cp/init.c
>>> @@ -1151,6 +1151,8 @@ sort_mem_initializers (tree t, tree mem_inits)
>>> /* Record the initialization. */
>>> TREE_VALUE (subobject_init) = TREE_VALUE (init);
>>> + /* Carry over the dummy TREE_TYPE node containing the source
>>> location. */
>>> + TREE_TYPE (subobject_init) = TREE_TYPE (init);
>>> next_subobject = subobject_init;
>>> }
>>> @@ -1367,6 +1369,10 @@ emit_mem_initializers (tree mem_inits)
>>> /* Initialize the data members. */
>>> while (mem_inits)
>>> {
>>> + /* If this initializer was explicitly provided, then the dummy
>>> TREE_TYPE
>>> + node contains the source location. */
>>> + iloc_sentinel ils (EXPR_LOCATION (TREE_TYPE (mem_inits)));
>>> +
>>> perform_member_init (TREE_PURPOSE (mem_inits),
>>> TREE_VALUE (mem_inits));
>>> mem_inits = TREE_CHAIN (mem_inits);
>>> diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
>>> index ab088874ba7..2f9b8786121 100644
>>> --- a/gcc/cp/parser.c
>>> +++ b/gcc/cp/parser.c
>>> @@ -15326,6 +15326,14 @@ cp_parser_mem_initializer_list (cp_parser* parser)
>>> {
>>> TREE_CHAIN (mem_initializer) = mem_initializer_list;
>>> mem_initializer_list = mem_initializer;
>>> +
>>> + /* We can't attach the source location of this initializer directly
>>> to
>>> + the list node, so we instead attach it to a dummy
>>> EMPTY_CLASS_EXPR
>>> + within the TREE_TYPE of the list node. */
>>> + TREE_TYPE (mem_initializer) = build0 (EMPTY_CLASS_EXPR, NULL_TREE);
>>> + SET_EXPR_LOCATION (TREE_TYPE (mem_initializer),
>>> + make_location (token->location,
>>> + token->location, input_location));
>>
>> Why not do this in cp_parser_mem_initializer?
>>
>> Also, use parser->lexer for the last argument to make_location.
>
> That's a much better spot for it :) Done and done. Does the following
> look OK after testing completes?
OK.
> -- >8 --
>
> Subject: [PATCH] c++: Member initializer list diagnostic locations [PR94024]
>
> This patch preserves the source locations of each node in a member
> initializer list so that during processing of the list we can set
> input_location appropriately for generally more accurate diagnostic
> locations. Since TREE_LIST nodes are tcc_exceptional, they can't have
> source locations, so we instead store the location in a dummy
> tcc_expression node within the TREE_TYPE of the list node.
>
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK to
> commit?
>
> gcc/cp/ChangeLog:
>
> PR c++/94024
> * init.c (sort_mem_initializers): Preserve TREE_TYPE of the
> member initializer list node.
> (emit_mem_initializers): Set input_location when performing each
> member initialization.
> * parser.c (cp_parser_mem_initializer): Attach the source
> location of this initializer to a dummy EMPTY_CLASS_EXPR
> within the TREE_TYPE of the list node.
> * pt.c (tsubst_initializer_list): Preserve TREE_TYPE of the
> member initializer list node.
>
> gcc/testsuite/ChangeLog:
>
> PR c++/94024
> * g++.dg/diagnostic/mem-init1.C: New test.
> ---
> gcc/cp/init.c | 6 +++++
> gcc/cp/parser.c | 13 ++++++++-
> gcc/cp/pt.c | 3 +++
> gcc/testsuite/g++.dg/diagnostic/mem-init1.C | 29 +++++++++++++++++++++
> 4 files changed, 50 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/g++.dg/diagnostic/mem-init1.C
>
> diff --git a/gcc/cp/init.c b/gcc/cp/init.c
> index cb9bd2dbfba..3f089404cf2 100644
> --- a/gcc/cp/init.c
> +++ b/gcc/cp/init.c
> @@ -1151,6 +1151,8 @@ sort_mem_initializers (tree t, tree mem_inits)
>
> /* Record the initialization. */
> TREE_VALUE (subobject_init) = TREE_VALUE (init);
> + /* Carry over the dummy TREE_TYPE node containing the source location. */
> + TREE_TYPE (subobject_init) = TREE_TYPE (init);
> next_subobject = subobject_init;
> }
>
> @@ -1367,6 +1369,10 @@ emit_mem_initializers (tree mem_inits)
> /* Initialize the data members. */
> while (mem_inits)
> {
> + /* If this initializer was explicitly provided, then the dummy TREE_TYPE
> + node contains the source location. */
> + iloc_sentinel ils (EXPR_LOCATION (TREE_TYPE (mem_inits)));
> +
> perform_member_init (TREE_PURPOSE (mem_inits),
> TREE_VALUE (mem_inits));
> mem_inits = TREE_CHAIN (mem_inits);
> diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
> index ab088874ba7..8b11e478c83 100644
> --- a/gcc/cp/parser.c
> +++ b/gcc/cp/parser.c
> @@ -15411,7 +15411,18 @@ cp_parser_mem_initializer (cp_parser* parser)
>
> in_base_initializer = 0;
>
> - return member ? build_tree_list (member, expression_list) : error_mark_node;
> + if (!member)
> + return error_mark_node;
> +
> + tree node = build_tree_list (member, expression_list);
> + /* We can't attach the source location of this initializer directly to
> + the list node, so we instead attach it to a dummy EMPTY_CLASS_EXPR
> + within the TREE_TYPE of the list node. */
> + TREE_TYPE (node) = build0 (EMPTY_CLASS_EXPR, NULL_TREE);
> + SET_EXPR_LOCATION (TREE_TYPE (node),
> + make_location (token->location,
> + token->location, parser->lexer));
> + return node;
> }
>
> /* Parse a mem-initializer-id.
> diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
> index 524c0bfe2d6..721eb5262d6 100644
> --- a/gcc/cp/pt.c
> +++ b/gcc/cp/pt.c
> @@ -26014,6 +26014,9 @@ tsubst_initializer_list (tree t, tree argvec)
> if (decl)
> {
> init = build_tree_list (decl, init);
> + /* Carry over the dummy TREE_TYPE node containing the source
> + location. */
> + TREE_TYPE (init) = TREE_TYPE (t);
> TREE_CHAIN (init) = inits;
> inits = init;
> }
> diff --git a/gcc/testsuite/g++.dg/diagnostic/mem-init1.C b/gcc/testsuite/g++.dg/diagnostic/mem-init1.C
> new file mode 100644
> index 00000000000..b749c72cd8b
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/diagnostic/mem-init1.C
> @@ -0,0 +1,29 @@
> +// PR c++/94024
> +// { dg-do compile }
> +
> +struct A {
> + A()
> + : a() // { dg-error "reference type" }
> + , b(1) // { dg-error "incompatible" }
> + , c(0) // { dg-bogus "" }
> + {}
> +
> + int &a;
> + int b[1];
> + char c;
> +};
> +
> +template<typename T, typename U>
> +struct B {
> + B()
> + : a() // { dg-error "reference type" }
> + , b(1) // { dg-error "incompatible" }
> + , c(0) // { dg-bogus "" }
> + {}
> +
> + T a;
> + U b;
> + char c;
> +};
> +
> +B<int&, int[1]> b;
>
More information about the Gcc-patches
mailing list