[Bug c++/11582] New: Odd error message with dynamically sized template arg printing

[Bug c++/11582] New: Odd error message with dynamically sized template arg printing

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582

           Summary: Odd error message with dynamically sized template arg
                    printing
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bangerth at dealii dot org
                CC: gcc-bugs at gcc dot gnu dot org,gdr at gcc dot gnu dot
                    org

Extracted from PR 6785: 
 
I guess this is totally irrelevant (because the code is invalid), but nevertheless: for this code 
------------------------------------------------- 
template <typename T> int  size(); 
template <int N>      void f(int (&)[N]); 
 
void g() { 
  int buf[size<int>()]; 
  f( buf ) ; 
} 
------------------------------------------------- 
we get the following error: 
tmp/gg> ../build-gcc/gcc-install/bin/c++ -c x.cc 
x.cc: In function `void g()': 
x.cc:6: error: no matching function for call to `f(int[size() [with T = int]()])' 
 
Note how we try to write the size of the array as an expression, which involves the 
call to a templated function, and where it tries to place the template arg when 
printing it. It is a little confusing to see the [with T=int] here, since T is nowhere referenced 
before or after, and the placing is odd. 
 
And then there is the duplicate () after the templates are printed. This can be seen here 
too: 
---------------------------------- 
int  size(); 
template <int N> void f(int (&)[N]); 
 
void g() { 
  int buf[size()]; 
  f( buf ) ; 
} 
------------------------------------- 
tmp/gg> ../build-gcc/gcc-install/bin/c++ -c x.cc 
x.cc: In function `void g()': 
x.cc:6: error: no matching function for call to `f(int[size()()])' 
 
I think that looks just cute ;-) 
 
W.

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[gdr at integrable-solutions dot net]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582



------- Additional Comments From gdr at integrable-solutions dot net  2003-07-18 22:52 -------
Subject: Re:  New: Odd error message with dynamically sized template arg printing

"bangerth at dealii dot org" <gcc-bugzilla@gcc.gnu.org> writes:

| ------------------------------------------------- 
| we get the following error: 
| tmp/gg> ../build-gcc/gcc-install/bin/c++ -c x.cc 
| x.cc: In function `void g()': 
| x.cc:6: error: no matching function for call to `f(int[size() [with T = int]()])' 
|  
| Note how we try to write the size of the array as an expression, which involves the 
| call to a templated function, and where it tries to place the template arg when 
| printing it. It is a little confusing to see the [with T=int] here, since T is nowhere referenced 
| before or after, and the placing is odd. 

I agree with you, that looks ugly.  
Fortunately, with the new pretty-printer being written, we should be
able to do better.  But before that, I need to get rid of some odd
diagnostic functions, which is what I'm currently doing.

[...]

| x.cc:6: error: no matching function for call to `f(int[size()()])' 
|  
| I think that looks just cute ;-) 

Again agreed.

We've been pulling out too important info, and trying hard to pull in
too irrelevant info.

-- Gaby

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[pinskia at physics dot uc dot edu]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582


pinskia at physics dot uc dot edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2003-07-19 02:31:38
               date|                            |


------- Additional Comments From pinskia at physics dot uc dot edu  2003-07-19 02:31 -------
I thought I saw the double pareneses problem in a different bug before but this error 
message is confusing.

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582



------- Additional Comments From bangerth at dealii dot org  2003-07-19 03:00 -------
Yeah, I thought of that other PR too when I opened this one. A brief search
finds PR 10345 for the double parentheses problem.

W.

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2003-07-19 02:31:38         |2003-08-17 12:43:09
               date|                            |
            Version|unknown                     |3.4


------- Additional Comments From pinskia at gcc dot gnu dot org  2003-08-17 12:43 -------
It is even worse now:
First example:
pr11582.cc: In function `void g()':
pr11582.cc:7: error: no matching function for call to `f(int[((long unsigned 
   int)((<anonymous>)size() [with T = int]()))])'

Second example:
pr11582.1.cc: In function `void g()':
pr11582.1.cc:7: error: no matching function for call to `f(int[((long unsigned 
   int)((<anonymous>)size()()))])'

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[dhazeghi at yahoo dot com]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582


dhazeghi at yahoo dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4                         |---

[Bug c++/11582] Odd error message with dynamically sized template arg printing

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-11-23 07:04 -------
Looks like this has not been fixed but looks closer to what is needed:
pr11582.cc:7: error: no matching function for call to `f(int[((long unsigned int)((int)size 
[with T = int]()))])'


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2003-08-17 12:43:09         |2003-11-23 07:04:15
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11582