[Bug c/50330] New: Misleading error message with struct declaration

[Bug c/50330] New: Misleading error message with struct declaration

[rui.maciel at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50330

             Bug #: 50330
           Summary: Misleading error message with struct declaration
    Classification: Unclassified
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: rui.maciel@gmail.com


struct t {
         int x;
}

int main(void)
{
         return 0;
}

This code, compiled with gcc, produces the following error message:

<message>
rui@Kubuntu:tmp$ gcc main.c
main.c:5:1: error: two or more data types in declaration specifiers
main.c: In function ‘main’:
main.c:7:10: error: incompatible types when returning type ‘int’ but ‘struct t’
was expected
</message>

The same code, when compiled with g++, produces the following error message:

<message>
rui@Kubuntu:tmp$ g++ main.c
main.c:1:1: error: new types may not be defined in a return type
main.c:1:1: note: (perhaps a semicolon is missing after the definition of ‘t’)
main.c:5:14: error: two or more data types in declaration of ‘main’
</message>

gcc's error message is cryptic and doesn't help the user.  g++'s error message,
on the other hand, although it is still cryptic it provides useful clues to the
user, which makes it considerably more helpful.  Nonetheless, both error
messages are needlessly cryptic and could be considerable improved, so that the
user gets a much clearer idea on where the error lies.

As a comparison, here is clang's error message:

<message>
rui@Kubuntu:tmp$ clang main.c
main.c:3:2: error: expected ';' after struct
}
 ^
 ;
1 error generated.
</message>

This error message is clear, concise and to the point. 

It would be great if GCC improved the error message for this scenario.

[Bug c/50330] Misleading error message with struct declaration

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50330

Jonathan Wakely <redi at gcc dot gnu.org> changed:

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

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-09-08 15:08:46 UTC ---
gcc 4.6 gives:
s.c:5:1: error: expected ';', identifier or '(' before 'int'

and g++ 4.6 gives:
s.c:3:1: error: expected ';' after struct definition

[Bug c/50330] Misleading error message with struct declaration

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50330

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|FIXED                       |DUPLICATE

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-09-08 15:16:35 UTC ---
marking as dup instead of FIXED

*** This bug has been marked as a duplicate of bug 45331 ***

[Bug c/50330] Misleading error message with struct declaration

[bugzilla at bsb dot me.uk]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50330

Ben Bacarisse <bugzilla at bsb dot me.uk> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bugzilla at bsb dot me.uk

--- Comment #3 from Ben Bacarisse <bugzilla at bsb dot me.uk> 2011-09-09 01:10:02 UTC ---
The fixed message (as reported) is not quite right.  It lists some, but not
all, of the tokens that are to be expected in this situation.  Basically, apart
from the semicolon, anything that can start a declarator is to be expected so
the list should include '*' as well.

I don't this is worth a new bug report, so I am just commenting here.