Hi!
The deducing this patchset added parsing of this specifier to
cp_parser_decl_specifier_seq unconditionally, but in the C++ grammar
this[opt] only appears in the parameter-declaration non-terminal, so
rather than checking in all the callers of cp_parser_decl_specifier_seq
except for cp_parser_parameter_declaration that this specifier didn't
appear I think it is far easier and closer to what the standard says
to only parse this specifier when called from
cp_parser_parameter_declaration.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2024-02-06 Jakub Jelinek <ja...@redhat.com>
PR c++/113788
* parser.cc (CP_PARSER_FLAGS_PARAMETER): New enumerator.
(cp_parser_decl_specifier_seq): Parse RID_THIS only if
CP_PARSER_FLAGS_PARAMETER is set in flags.
(cp_parser_parameter_declaration): Or in CP_PARSER_FLAGS_PARAMETER
when calling cp_parser_decl_specifier_seq.
* g++.dg/parse/pr113788.C: New test.
--- gcc/cp/parser.cc.jj 2024-01-17 10:34:45.337660930 +0100
+++ gcc/cp/parser.cc 2024-02-06 18:31:35.587193903 +0100
@@ -2088,7 +2088,9 @@ enum
/* When parsing of the noexcept-specifier should be delayed. */
CP_PARSER_FLAGS_DELAY_NOEXCEPT = 0x40,
/* When parsing a consteval declarator. */
- CP_PARSER_FLAGS_CONSTEVAL = 0x80
+ CP_PARSER_FLAGS_CONSTEVAL = 0x80,
+ /* When parsing a parameter declaration. */
+ CP_PARSER_FLAGS_PARAMETER = 0x100
};
/* This type is used for parameters and variables which hold
@@ -16342,7 +16344,7 @@ cp_parser_decl_specifier_seq (cp_parser*
/* Special case for "this" specifier, indicating a parm is an xobj parm.
The "this" specifier must be the first specifier in the declaration,
after any attributes. */
- if (token->keyword == RID_THIS)
+ if (token->keyword == RID_THIS && (flags & CP_PARSER_FLAGS_PARAMETER))
{
cp_lexer_consume_token (parser->lexer);
if (token != first_specifier)
@@ -25607,7 +25609,7 @@ cp_parser_parameter_declaration (cp_pars
/* Parse the declaration-specifiers. */
cp_token *decl_spec_token_start = cp_lexer_peek_token (parser->lexer);
cp_parser_decl_specifier_seq (parser,
- flags,
+ flags | CP_PARSER_FLAGS_PARAMETER,
&decl_specifiers,
&declares_class_or_enum);
--- gcc/testsuite/g++.dg/parse/pr113788.C.jj 2024-02-06 18:40:29.553791028
+0100
+++ gcc/testsuite/g++.dg/parse/pr113788.C 2024-02-06 18:41:23.326045703
+0100
@@ -0,0 +1,20 @@
+// PR c++/113788
+// { dg-do compile { target c++11 } }
+
+struct S { int a, b; };
+struct U {
+ void foo () { this int g = 1; } // { dg-error "expected ';' before
'int'" }
+};
+this auto h = 1; // { dg-error "expected unqualified-id
before 'this'" }
+
+int
+main ()
+{
+ S s = { 1, 2 };
+ short t[3] = { 3, 4, 5 };
+ this auto &[a, b] = s; // { dg-error "invalid use of 'this' in
non-member function" }
+ this auto &[c, d, e] = t; // { dg-error "invalid use of 'this' in
non-member function" }
+ this int f = 1; // { dg-error "invalid use of 'this' in
non-member function" }
+ for (this auto &i : t) // { dg-error "invalid use of 'this' in
non-member function" }
+ ; // { dg-error "expected" }
+} // { dg-error "expected" }
Jakub
