Message ID | Zc8pMnDUZEXGVqep@tucnak |
---|---|
State | New |
Headers | show |
Series | c++: Diagnose this specifier on template parameters [PR113929] | expand |
On 2/16/24 04:21, Jakub Jelinek wrote: > Hi! > > For template parameters, the optional this specifier is in the grammar > template-parameter-list -> template-parameter -> parameter-declaration, > just [dcl.fct/6] says that it is only valid in parameter-list of certain > functions. So, unlike the case of decl-specifier-seq used in non-terminals > other than parameter-declaration, I think it is better not to fix this > by > cp_parser_decl_specifier_seq (parser, > - flags | CP_PARSER_FLAGS_PARAMETER, > + flags | (template_parameter_p ? 0 > + : CP_PARSER_FLAGS_PARAMETER), > &decl_specifiers, > &declares_class_or_enum); > which would be pretending it isn't in the grammar, but by diagnosing it > separately, which is what the following patch does. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK. > 2024-02-16 Jakub Jelinek <jakub@redhat.com> > > PR c++/113929 > * parser.cc (cp_parser_parameter_declaration): Diagnose this specifier > on template parameter declaration. > > * g++.dg/parse/pr113929.C: New test. > > --- gcc/cp/parser.cc.jj 2024-02-15 17:33:11.641453437 +0100 > +++ gcc/cp/parser.cc 2024-02-15 17:40:29.592447265 +0100 > @@ -25724,8 +25724,15 @@ cp_parser_parameter_declaration (cp_pars > for a C-style variadic function. */ > token = cp_lexer_peek_token (parser->lexer); > > - bool const xobj_param_p > + bool xobj_param_p > = decl_spec_seq_has_spec_p (&decl_specifiers, ds_this); > + if (xobj_param_p && template_parm_p) > + { > + error_at (decl_specifiers.locations[ds_this], > + "%<this%> specifier in template parameter declaration"); > + xobj_param_p = false; > + decl_specifiers.locations[ds_this] = 0; > + } > > bool diag_xobj_parameter_pack = false; > if (xobj_param_p && (declarator && declarator->parameter_pack_p)) > --- gcc/testsuite/g++.dg/parse/pr113929.C.jj 2024-02-15 17:43:18.500129688 +0100 > +++ gcc/testsuite/g++.dg/parse/pr113929.C 2024-02-15 17:42:54.564458109 +0100 > @@ -0,0 +1,7 @@ > +// PR c++/113929 > +// { dg-do compile } > + > +template <this int C> // { dg-error "'this' specifier in template parameter declaration" } > +struct S {}; > +template <int N, this int C> // { dg-error "'this' specifier in template parameter declaration" } > +struct T {}; > > Jakub >
--- gcc/cp/parser.cc.jj 2024-02-15 17:33:11.641453437 +0100 +++ gcc/cp/parser.cc 2024-02-15 17:40:29.592447265 +0100 @@ -25724,8 +25724,15 @@ cp_parser_parameter_declaration (cp_pars for a C-style variadic function. */ token = cp_lexer_peek_token (parser->lexer); - bool const xobj_param_p + bool xobj_param_p = decl_spec_seq_has_spec_p (&decl_specifiers, ds_this); + if (xobj_param_p && template_parm_p) + { + error_at (decl_specifiers.locations[ds_this], + "%<this%> specifier in template parameter declaration"); + xobj_param_p = false; + decl_specifiers.locations[ds_this] = 0; + } bool diag_xobj_parameter_pack = false; if (xobj_param_p && (declarator && declarator->parameter_pack_p)) --- gcc/testsuite/g++.dg/parse/pr113929.C.jj 2024-02-15 17:43:18.500129688 +0100 +++ gcc/testsuite/g++.dg/parse/pr113929.C 2024-02-15 17:42:54.564458109 +0100 @@ -0,0 +1,7 @@ +// PR c++/113929 +// { dg-do compile } + +template <this int C> // { dg-error "'this' specifier in template parameter declaration" } +struct S {}; +template <int N, this int C> // { dg-error "'this' specifier in template parameter declaration" } +struct T {};