[Bug c++/35334] New: [4.1/4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[Bug c++/35334] New: [4.1/4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[reichelt at gcc dot gnu dot org]

A broken diagnostic is issued for the following invalid code snippet since
at least GCC 2.95.3:

====================================================
void foo(__complex__ unsigned int i)
{
  ((__complex__ int)i)();
}
====================================================

bug.cc: In function 'void foo(unsigned int __complex__)':
bug.cc:3: error: '#'complex_expr' not supported by dump_expr#<expression
error>' cannot be used as a function


-- 
           Summary: [4.1/4.2/4.3/4.4 regression] Broken diagnostic for
                    complex cast
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: diagnostic, monitored
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.1/4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[rguenth at gcc dot gnu dot org]

------- Comment #1 from rguenth at gcc dot gnu dot org  2008-02-24 22:01 -------
Confirmed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Priority|P3                          |P2
   Last reconfirmed|0000-00-00 00:00:00         |2008-02-24 22:01:18
               date|                            |
   Target Milestone|---                         |4.2.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.1/4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[jsm28 at gcc dot gnu dot org]

------- Comment #2 from jsm28 at gcc dot gnu dot org  2008-05-19 20:25 -------
4.2.4 is being released, changing milestones to 4.2.5.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.2.4                       |4.2.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[jsm28 at gcc dot gnu dot org]

------- Comment #3 from jsm28 at gcc dot gnu dot org  2008-07-04 23:02 -------
Closing 4.1 branch.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.1/4.2/4.3/4.4 regression]|[4.2/4.3/4.4 regression]
                   |Broken diagnostic for       |Broken diagnostic for
                   |complex cast                |complex cast


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[manu at gcc dot gnu dot org]

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------- Comment #4 from manu at gcc dot gnu dot org  2008-10-25 14:52 -------
The C front-end prints:

error: called object ‘(int __complex__){(int)__real__ (i), (int)__imag__ (i)}’
is not a function

which is not great either.

We could try to dump the complex expression as a CONVERT_EXPR:

error: ‘(int __complex__)((int)__real__ i)’ cannot be used as a function

or we can just print something like 

error: ‘__complex__ expression’ cannot be used as a function

I think I prefer the latter. Any opinions?


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |manu at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[manu at gcc dot gnu dot org]

------- Comment #5 from manu at gcc dot gnu dot org  2008-11-03 10:38 -------
What we want to do about this?

Anyway, P2 is probably is too high severity. This obviously doesn't have a high
priority. And I would argue that this is probably not a regression.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[jakub at gcc dot gnu dot org]

------- Comment #6 from jakub at gcc dot gnu dot org  2008-11-03 11:04 -------
I think the "cannot be used as a function" error should print the exact object
only if it is a DECL_P, otherwise just print error: expression cannot be used
as a function".  Imagine if the object is a 100KB statement expression, do we
want to print that?  When we have to start/end location information, we'd just
print a caret range.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[manu at gcc dot gnu dot org]

------- Comment #7 from manu at gcc dot gnu dot org  2008-11-03 11:12 -------
(In reply to comment #6)
> I think the "cannot be used as a function" error should print the exact object
> only if it is a DECL_P, otherwise just print error: expression cannot be used
> as a function".  Imagine if the object is a 100KB statement expression, do we
> want to print that?  When we have to start/end location information, we'd just
> print a caret range.

This doesn't only apply to that particular error but anywhere that tries to
print a complex_expr. So it cannot be solved at that level. It must be solved
inside pretty-printer.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[jakub at gcc dot gnu dot org]

------- Comment #8 from jakub at gcc dot gnu dot org  2008-11-11 14:08 -------
Patch posted.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2008-
                   |                            |11/msg00415.html
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2008-02-24 22:01:18         |2008-11-11 14:08:19
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] [4.2/4.3/4.4 regression] Broken diagnostic for complex cast

[jakub at gcc dot gnu dot org]

------- Comment #9 from jakub at gcc dot gnu dot org  2008-11-12 08:20 -------
Subject: Bug 35334

Author: jakub
Date: Wed Nov 12 08:18:45 2008
New Revision: 141783

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=141783
Log:
        PR c++/35334
        * c-pretty-print.c (pp_c_complex_expr): New function.
        (pp_c_postfix_expression) <case COMPLEX_EXPR>: Call it.

        * error.c (dump_expr): Handle COMPLEX_EXPR.

        * gcc.dg/pr35334.c: New test.
        * g++.dg/other/error29.C: New test.

Added:
    trunk/gcc/testsuite/g++.dg/other/error29.C
    trunk/gcc/testsuite/gcc.dg/pr35334.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/c-pretty-print.c
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/error.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334

[Bug c++/35334] Broken diagnostic for complex cast

[reichelt at gcc dot gnu dot org]

------- Comment #10 from reichelt at gcc dot gnu dot org  2008-12-31 14:09 -------
This bug is not a regression.
Closing it because it's now fixed on trunk.


-- 

reichelt at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
            Summary|[4.2/4.3 regression] Broken |Broken diagnostic for
                   |diagnostic for complex cast |complex cast
   Target Milestone|4.2.5                       |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35334