[Bug c++/37088] New: Functions with default parameters not correctly handled inside templates.

[Bug c++/37088] New: Functions with default parameters not correctly handled inside templates.

[tmsriram at google dot com]

For this simple program (test.cc):
-------------------------------------------------------------------------
template <typename Pred>
void AssertPred(Pred pred) {
 pred("x", "y");
}

bool pred4(const char *, const char *, const char *x = "", const char *y = "");
bool pred2(const char *, const char *);

void foof() {
  AssertPred(pred2);
  AssertPred(pred4);
}
-----------------------------------------------------------------------------


> $gcc421 -c test.ii (Success with gcc-4.2.1)


> $gcc431  -c test.ii (Failure with gcc-4.3.1)

test.ii: In function 'void AssertPred(Pred) [with Pred = bool (*)(const char*,
const char*, const char*, const char*)]':
test.ii:   instantiated from here
test.ii: error: too few arguments to function


-- 
           Summary: Functions with default parameters not correctly handled
                    inside templates.
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: tmsriram at google dot com
 GCC build triplet: x86_64
  GCC host triplet: x86_64
GCC target triplet: x86_64


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37088

[Bug c++/37088] Functions with default parameters not correctly handled inside templates.

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2008-08-11 22:45 -------
Hmm, I don't think default parameters are taken into account with function
pointers.   I think this was a GCC "undocumented extension" (aka bug) that was
fixed in 4.3.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|major                       |normal


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37088

[Bug c++/37088] Functions with default parameters not correctly handled inside templates.

[bangerth at dealii dot org]

------- Comment #2 from bangerth at dealii dot org  2008-08-13 16:21 -------
(In reply to comment #0)
> bool pred4(const char *, const char *, const char *x = "", const char *y = "");

The type of pred4 is still
  bool (*) (const char *, const char *, const char *x, const char *)
and so when you pass this function through a pointer it can't be called with
only two parameters. 

Andrew is right that this used to be one of the many ill-conceived gcc
extensions.

W.


-- 

bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bangerth at dealii dot org
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37088

[Bug c++/37088] Functions with default parameters not correctly handled inside templates.

[pinskia at gcc dot gnu dot org]

------- Comment #3 from pinskia at gcc dot gnu dot org  2009-02-10 22:03 -------
*** Bug 39136 has been marked as a duplicate of this bug. ***


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |fang at csl dot cornell dot
                   |                            |edu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37088