[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[schaub-johannes at web dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

--- Comment #3 from Johannes Schaub <schaub-johannes at web dot de> 2010-10-30 09:41:36 UTC ---
(In reply to comment #2)
> (In reply to comment #1)
> > (In reply to comment #0)
> > > Fails to compile, but should work:
> > > 
> > > struct A { 
> > >   char x[4]; 
> > >   A():x("bug") { } 
> > > };
> > > 
> > > Error i get is:
> > > 
> > > "main.cpp:3: error: array used as initializer"
> > > 
> > 
> > Why do you think it should work?  
> > For example, the following equivalent code is invalid as well:
> > 
> > char x [4] ("bug");
> > 
> 
> This code is equivalent and is valid. At least, I don't see the Standard
> forbidding it. GCC is the only compiler I tested (comeau/edg, clang) that
> rejects it.

I'm not actually sure anymore about the validity of this code. One can make a
point about the initializer not being a mere string literal.

At least the draft n3126 makes a difference of this, in that an initializer
like "({a, b, c})" is not regarded as a braced-init-list, but rather as a
parenthesized expression-list where the initializer list is handed as one
argument. So I'm unsure whether an initializer like `("foo")` should be
regarded as a string literal or not.

I think I will send an issue report about this.

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[schaub.johannes at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

--- Comment #4 from Johannes Schaub <schaub.johannes at googlemail dot com> 2011-05-14 16:18:58 UTC ---
(In reply to comment #3)
> (In reply to comment #2)
> > (In reply to comment #1)
> > > (In reply to comment #0)
> > > > Fails to compile, but should work:
> > > > 
> > > > struct A { 
> > > >   char x[4]; 
> > > >   A():x("bug") { } 
> > > > };
> > > > 
> > > > Error i get is:
> > > > 
> > > > "main.cpp:3: error: array used as initializer"
> > > > 
> > > 
> > > Why do you think it should work?  
> > > For example, the following equivalent code is invalid as well:
> > > 
> > > char x [4] ("bug");
> > > 
> > 
> > This code is equivalent and is valid. At least, I don't see the Standard
> > forbidding it. GCC is the only compiler I tested (comeau/edg, clang) that
> > rejects it.
> 
> I'm not actually sure anymore about the validity of this code. One can make a
> point about the initializer not being a mere string literal.
> 
> At least the draft n3126 makes a difference of this, in that an initializer
> like "({a, b, c})" is not regarded as a braced-init-list, but rather as a
> parenthesized expression-list where the initializer list is handed as one
> argument. So I'm unsure whether an initializer like `("foo")` should be
> regarded as a string literal or not.
> 
> I think I will send an issue report about this.

Subsequent discussion with Jason showed that this is covered by 8.5p13:

   The form of initialization (using parentheses or =) is generally 
   insignificant, but does matter when the initializer or the entity 
   being initialized has a class type;

As this is an array, the text in the Standard in general has to be interpreted
that a "=" or a "(..)" initializer are equivalent, unless otherwise stated. 

So this is indeed a GCC bug (both that it rejects the member initialization and
the parenthesized non-member initialization).

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
             Target|i686-pc-linux-gnu           |
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-01-28
               Host|i686-pc-linux-gnu           |
     Ever Confirmed|0                           |1
      Known to fail|                            |4.7.0

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-01-28 05:43:59 UTC ---
Confirmed.

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|gcc-bugs at gcc dot gnu.org        |
           Assignee|unassigned at gcc dot gnu.org      |paolo.carlini at oracle dot com
   Target Milestone|---                         |4.10.0

--- Comment #6 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Mine.

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[paolo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

--- Comment #7 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Wed Jun  4 22:30:39 2014
New Revision: 211248

URL: http://gcc.gnu.org/viewcvs?rev=211248&root=gcc&view=rev
Log:
/cp
2014-06-04  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/43453
    * typeck.c (cp_build_modify_expr): Handle array of characters
    initialized by a string literal.
    * decl.c (check_initializer): Handle parenthesized string literal
    as initializer.
    * typeck2.c (store_init_value): Remove redundant check.

/testsuite
2014-06-04  Paolo Carlini  <paolo.carlini@oracle.com>

    PR c++/43453
    * g++.dg/init/pr43453.C: New.

Added:
    trunk/gcc/testsuite/g++.dg/init/pr43453.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/decl.c
    trunk/gcc/cp/typeck.c
    trunk/gcc/cp/typeck2.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[paolo.carlini at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED
           Assignee|paolo.carlini at oracle dot com    |unassigned at gcc dot gnu.org

--- Comment #8 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Fixed for 4.10.0.

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

--- Comment #9 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Thu Jun  5 20:55:44 2014
New Revision: 211290

URL: http://gcc.gnu.org/viewcvs?rev=211290&root=gcc&view=rev
Log:
    PR c++/43453
    * decl.c (check_initializer): Collapse a TREE_LIST here.
    * typeck2.c (store_init_value): Not here.

Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/decl.c
    trunk/gcc/cp/typeck2.c

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[schaub-johannes at web dot de]

------- Comment #2 from schaub-johannes at web dot de  2010-08-28 14:39 -------
(In reply to comment #1)
> (In reply to comment #0)
> > Fails to compile, but should work:
> > 
> > struct A { 
> >   char x[4]; 
> >   A():x("bug") { } 
> > };
> > 
> > Error i get is:
> > 
> > "main.cpp:3: error: array used as initializer"
> > 
> 
> Why do you think it should work?  
> For example, the following equivalent code is invalid as well:
> 
> char x [4] ("bug");
> 

This code is equivalent and is valid. At least, I don't see the Standard
forbidding it. GCC is the only compiler I tested (comeau/edg, clang) that
rejects it.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453

[Bug c++/43453] Initialization of char array with string literal fails in mem-initializer

[giecrilj at stegny dot 2a dot pl]

------- Comment #1 from giecrilj at stegny dot 2a dot pl  2010-08-27 18:06 -------
(In reply to comment #0)
> Fails to compile, but should work:
> 
> struct A { 
>   char x[4]; 
>   A():x("bug") { } 
> };
> 
> Error i get is:
> 
> "main.cpp:3: error: array used as initializer"
> 

Why do you think it should work?  
For example, the following equivalent code is invalid as well:

char x [4] ("bug");


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43453