[Bug c++/31489] error says struct when it should say class

[Bug c++/31489] error says struct when it should say class

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |paolo.carlini at oracle dot
                   |gnu.org                     |com

--- Comment #3 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-09-27 10:06:09 UTC ---
I just discovered that actually we *do* have machinery to do this, in general
terms (see CLASSTYPE_DECLARED_CLASS, used by eg, class_key_or_enum_as_string).
But cp_parser_elaborated_type_specifier doesn't use it, ie doesn't set
CLASSTYPE_DECLARED_CLASS (at variance with cp_parser_class_head). Thus
something like the following patchlet should do the trick. That said, Andrew
has a point of course, for its second example we would say struct or class,
whichever comes last in the redeclaration. All in all, seems an improvement to
me, if the below works pretty well I'm going to submit it.

/////////////

Index: parser.c
===================================================================
--- parser.c    (revision 179242)
+++ parser.c    (working copy)
@@ -13423,8 +13423,15 @@ cp_parser_elaborated_type_specifier (cp_parser* pa
     }

   if (tag_type != enum_type)
-    cp_parser_check_class_key (tag_type, type);
+    {
+      /* Indicate whether this class was declared as a `class' or as a
+        `struct'.  */
+      if (TREE_CODE (type) == RECORD_TYPE)
+       CLASSTYPE_DECLARED_CLASS (type) = (tag_type == class_type);

+      cp_parser_check_class_key (tag_type, type);
+    }
+
   /* A "<" cannot follow an elaborated type specifier.  If that
      happens, the user was probably trying to form a template-id.  */
   cp_parser_check_for_invalid_template_id (parser, type, token->location);

[Bug c++/31489] error says struct when it should say class

[paolo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489

--- Comment #4 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> 2011-09-27 21:52:23 UTC ---
Author: paolo
Date: Tue Sep 27 21:52:19 2011
New Revision: 179293

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=179293
Log:
/cp
2011-09-27  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/31489
    * parser.c (cp_parser_elaborated_type_specifier): For RECORD_TYPE,
    set CLASSTYPE_DECLARED_CLASS.

/testsuite
2011-09-27  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/31489
    * g++.dg/parse/error40.C: New.
    * g++.dg/warn/incomplete1.C: Adjust.

Added:
    trunk/gcc/testsuite/g++.dg/parse/error40.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/parser.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/warn/incomplete1.C

[Bug c++/31489] error says struct when it should say class

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
                 CC|gcc-bugs at gcc dot gnu.org |
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #5 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-09-27 21:54:26 UTC ---
Fixed for 4.7.0.

[Bug c++/31489] New: error says struct when it should say class

[jg at jguk dot org]

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[-- Attachment #1: Type: text/plain, Size: 1106 bytes --]

When a forward declared class is not found the error message describes it
incorrectly as a struct. See below for an example.

I'd like to submit a patch to correctly display class. Let me know if such a
patch would be considered.

$ g++ -Wall -ggdb -O0 -o t test6.cpp
test6.cpp: In function ‘int main()’:
test6.cpp:8: error: invalid use of undefined type ‘struct foobar’
test6.cpp:4: error: forward declaration of ‘struct foobar’

File contains:
=====================================
// g++ -Wall -ggdb -O0 -o t test6.cpp


class foobar;

int main()
{
        foobar * o = new foobar;
}
====================================


-- 
           Summary: error says struct when it should say class
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jg at jguk dot org
 GCC build triplet: i686-gnu-linux
  GCC host triplet: i686-gnu-linux
GCC target triplet: i686-gnu-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489

[Bug c++/31489] error says struct when it should say class

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2007-04-06 00:09 -------
I don't think this matters anyways as class == struct and can be used
interchangably for tags.

if you summit a patch, see what this shows you:
struct foobar;

int main()
{
        foobar * o = new foobar;
}

Or even this:

struct foobar;
class foobar;

int main()
{
        foobar * o = new foobar;
}

Since all three are the same code, so it is weird not to have struct == class
here really.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489

[Bug c++/31489] error says struct when it should say class

[bangerth at dealii dot org]

------- Comment #2 from bangerth at dealii dot org  2007-04-07 16:23 -------
Confirmed.

I think a patch would be of interest. Maybe one could just tweak
the error to read

x.cc:5: error: invalid use of undefined type 'foobar'
x.cc:1: error: forward declaration of struct or class 'foobar'


-- 

bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-04-07 16:23:28
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31489