Thanks for the feedback. I am attatching fixed patch as a file.
Regards
Franciszek
On Mon, 19 Aug 2024, 18:32 Jason Merrill, <ja...@redhat.com> wrote:
> On 8/19/24 12:01 PM, Jason Merrill wrote:
> > On 8/19/24 6:01 AM, Jonathan Wakely wrote:
> >> On 05/08/24 09:32 +0200, Franciszek Witt wrote:
> >>> Author: Franciszek Witt <franek.w...@gmail.com>
> >>> Date: Mon Aug 5 09:00:35 2024 +0200
> >>>
> >>> c++: [PR101232]
> >>
> >> The line above should be the first line of your Git commit message,
> >> which should be in the form "component: Summary of change [PRnnnn]"
> >> The Subject: of your email seems like it should be repeated here
> >> (although something shorter would be even nicer, if possible).
> >> https://cbea.ms/git-commit/
> >>
> >>
> >>> PR c++/101232
> >>>
> >>> gcc/cp/ChangeLog:
> >>>
> >>> * parser.cc (cp_parser_postfix_expression): Commit to the
> >>> parse in case we know its either a cast or invalid syntax.
> >>> (cp_parser_braced_list): Add a heuristic to inform about
> >>> missing comma or operator.
> >>
> >> The ChangeLog part of the commit message should follow the rules in
> >> the GNU Coding Standards:
> >> https://www.gnu.org/prep/standards/html_node/Style-of-Change-Logs.html
> >>
> >> Specifically, they should be wrapped to fit in an 80 column terminal
> >> window. I think wrapping around 76 columns is common. Please add line
> >> breaks here, e.g.
> >>
> >> * parser.cc (cp_parser_postfix_expression): Commit to the
> >> parse in case we know its either a cast or invalid syntax.
> >> (cp_parser_braced_list): Add a heuristic to inform about
> >> missing comma or operator.
> >>
> >> (but with a leading TAB, not spaces).
> >
> > Agreed. In addition, we need DCO certification or copyright assignment
> > (https://gcc.gnu.org/contribute.html#legal).
> >
> > Also, the patch itself was corrupted by word wrap in your mail client,
> > so it doesn't apply, e.g.:
> >
> >> @@ -7881,8 +7881,13 @@ cp_parser_postfix_expression (cp_parser
> >> *parser, bool address_p, bool cast_p,
> >
> > https://www.kernel.org/doc/html/latest/process/email-clients.html has
> > some tips for avoiding word wrap, or you can just attach the patch
> > instead of pasting it inline.
> >
> >> + /* This is just a heuristic. */
> >
> > Two spaces after the .
> >
> >> + inform (finish_loc, + "probably missing a comma
> >> or an operator before");
> >
> > The string should line up after the ( on the previous line.
> >
> > We might as well also put this inform under the
> > cp_parser_skip_to_closing_brace check; if there's no } at all, the
> > problem isn't a missing comma...
>
> Also, error59 seems like an error-recovery regression:
>
> > +++ b/gcc/testsuite/g++.dg/parse/error59.C
> > @@ -3,4 +3,4 @@
> > void foo()
> > {
> > (struct {}x){}; // { dg-error "" }
> > -}
> > +} // { dg-excess-errors "" }
>
> as we now get more of an error cascade. Perhaps also check the return
> value of the earlier require_open and don't skip_to_closing_brace if it
> failed?
>
> Jason
>
>
From 36b228ae1c8888ee84e8363fdf772f44521e1bd0 Mon Sep 17 00:00:00 2001
From: Franciszek Witt <franek.w...@gmail.com>
Date: Tue, 20 Aug 2024 14:34:01 +0200
Subject: [PATCH v4] c++: Improve error messages related to parsing a
postfix expression [PR101232]
PR c++/101232
gcc/cp/ChangeLog:
* parser.cc (cp_parser_postfix_expression): Commit to the
parse in case we know its either a cast or invalid syntax.
(cp_parser_braced_list): Add a heuristic to inform about
missing comma or operator.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/initlist-err1.C: New test.
* g++.dg/cpp0x/initlist-err2.C: New test.
* g++.dg/cpp0x/initlist-err3.C: New test.
Signed-off-by: Franciszek Witt <franek.w...@gmail.com>
---
gcc/cp/parser.cc | 23 +++++++++++++++++-----
gcc/testsuite/g++.dg/cpp0x/initlist-err1.C | 11 +++++++++++
gcc/testsuite/g++.dg/cpp0x/initlist-err2.C | 11 +++++++++++
gcc/testsuite/g++.dg/cpp0x/initlist-err3.C | 11 +++++++++++
4 files changed, 51 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-err1.C
create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-err2.C
create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-err3.C
diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
index 1dd0efaf963..d7189c27b0d 100644
--- a/gcc/cp/parser.cc
+++ b/gcc/cp/parser.cc
@@ -7881,8 +7881,13 @@ cp_parser_postfix_expression (cp_parser *parser, bool address_p, bool cast_p,
--parser->prevent_constrained_type_specifiers;
/* Parse the cast itself. */
if (!cp_parser_error_occurred (parser))
- postfix_expression
- = cp_parser_functional_cast (parser, type);
+ {
+ if (cp_lexer_next_token_is (parser->lexer, CPP_OPEN_BRACE))
+ /* This can only be a cast. */
+ cp_parser_commit_to_topmost_tentative_parse (parser);
+ postfix_expression
+ = cp_parser_functional_cast (parser, type);
+ }
/* If that worked, we're done. */
if (cp_parser_parse_definitely (parser))
break;
@@ -26332,7 +26337,7 @@ cp_parser_braced_list (cp_parser *parser, bool *non_constant_p /*=nullptr*/)
/* Consume the `{' token. */
matching_braces braces;
- braces.require_open (parser);
+ bool found_opening_brace = braces.require_open (parser);
/* Create a CONSTRUCTOR to represent the braced-initializer. */
initializer = make_node (CONSTRUCTOR);
/* If it's not a `}', then there is a non-trivial initializer. */
@@ -26350,8 +26355,16 @@ cp_parser_braced_list (cp_parser *parser, bool *non_constant_p /*=nullptr*/)
else if (non_constant_p)
*non_constant_p = false;
/* Now, there should be a trailing `}'. */
- location_t finish_loc = cp_lexer_peek_token (parser->lexer)->location;
- braces.require_close (parser);
+ cp_token * token = cp_lexer_peek_token (parser->lexer);
+ location_t finish_loc = token->location;
+ /* The part with CPP_SEMICOLON is just a heuristic. */
+ if (!braces.require_close (parser) && token->type != CPP_SEMICOLON
+ && found_opening_brace && cp_parser_skip_to_closing_brace (parser))
+ {
+ cp_lexer_consume_token (parser->lexer);
+ inform (finish_loc,
+ "probably missing a comma or an operator before");
+ }
TREE_TYPE (initializer) = init_list_type_node;
recompute_constructor_flags (initializer);
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-err1.C b/gcc/testsuite/g++.dg/cpp0x/initlist-err1.C
new file mode 100644
index 00000000000..6ea8afb3273
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist-err1.C
@@ -0,0 +1,11 @@
+// PR c++/101232
+// { dg-do compile { target c++11 } }
+
+struct X {
+ int a;
+ int b;
+};
+
+void f() {
+ auto x = X{ 1, 2; }; // { dg-error "21:" }
+} // { dg-prune-output "expected declaration" }
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-err2.C b/gcc/testsuite/g++.dg/cpp0x/initlist-err2.C
new file mode 100644
index 00000000000..227f519dc19
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist-err2.C
@@ -0,0 +1,11 @@
+// PR c++/101232
+// { dg-do compile { target c++11 } }
+
+struct X {
+ int a;
+ int b;
+};
+
+void f() {
+ auto x = X{ 1 2 }; // { dg-error "19:.*probably" }
+}
diff --git a/gcc/testsuite/g++.dg/cpp0x/initlist-err3.C b/gcc/testsuite/g++.dg/cpp0x/initlist-err3.C
new file mode 100644
index 00000000000..b77ec9bf4e9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/initlist-err3.C
@@ -0,0 +1,11 @@
+// PR c++/101232
+// { dg-do compile { target c++11 } }
+
+struct X {
+ int a;
+ int b;
+};
+
+void f() {
+ auto x = X{ 1, {2 }; // { dg-error "expected.*before" }
+}
--
2.34.1
