[Bug c++/113812] New: Comma expression parsed as declaration when ambiguous type name cast is present

[Bug c++/113812] New: Comma expression parsed as declaration when ambiguous type name cast is present

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113812

            Bug ID: 113812
           Summary: Comma expression parsed as declaration when ambiguous
                    type name cast is present
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

void f()
{
    int(x), a, b, c, d, e, f, g, h, etc;
    int(x), a, b, c, d, e, f, g, h, etc, (new int);
}

Clang parses this fine, but GCC errors out, complaining that:

<source>: In function 'void f()':
<source>:4:9: error: redeclaration of 'int x'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |         ^
<source>:3:9: note: 'int x' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |         ^
<source>:4:13: error: redeclaration of 'int a'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |             ^
<source>:3:13: note: 'int a' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |             ^
<source>:4:16: error: redeclaration of 'int b'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                ^
<source>:3:16: note: 'int b' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                ^
<source>:4:19: error: redeclaration of 'int c'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                   ^
<source>:3:19: note: 'int c' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                   ^
<source>:4:22: error: redeclaration of 'int d'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                      ^
<source>:3:22: note: 'int d' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                      ^
<source>:4:25: error: redeclaration of 'int e'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                         ^
<source>:3:25: note: 'int e' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                         ^
<source>:4:28: error: redeclaration of 'int f'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                            ^
<source>:3:28: note: 'int f' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                            ^
<source>:4:31: error: redeclaration of 'int g'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                               ^
<source>:3:31: note: 'int g' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                               ^
<source>:4:34: error: redeclaration of 'int h'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                                  ^
<source>:3:34: note: 'int h' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                                  ^
<source>:4:37: error: redeclaration of 'int etc'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                                     ^~~
<source>:3:37: note: 'int etc' previously declared here
    3 |     int(x), a, b, c, d, e, f, g, h, etc;
      |                                     ^~~
<source>:4:43: error: expected unqualified-id before 'new'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                                           ^~~
<source>:4:43: error: expected ')' before 'new'
    4 |     int(x), a, b, c, d, e, f, g, h, etc, (new int);
      |                                          ~^~~
      |                                           )

It appears that GCC is treating the second statement in the function as a
declaration instead of a comma expression, which Clang does.

[Bug c++/113812] Comma expression parsed as declaration when ambiguous type name cast is present

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113812

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I suspect this is a dup of bug 29834.

[Bug c++/113812] Comma expression parsed as declaration when ambiguous type name cast is present

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113812

--- Comment #2 from Gabriel Ravier <gabravier at gmail dot com> ---
Also I guess this is a simpler minimal example:

void f(int x)
{
    int(x), 0;
}

[Bug c++/113812] Comma expression parsed as declaration when ambiguous type name cast is present

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113812

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |DUPLICATE
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Yes this is a dup of bug 29834.

*** This bug has been marked as a duplicate of bug 29834 ***