Axel Naumann wrote:
This code compiles fine with gccxml, but const_container class
description doesn't contain artificial default constructor. At the
same time, it contains default copy constructor.
I am not C++ expert, but I think the class should have default
constructor.
I believe you're not testing what you think you are. Check this code
out, e.g. with GCC 4.3.1, slightly modified from your code:
$ cat gccxmlml.cxx
struct const_item{ const int values[10]; };
void test_const_item() { const_item x;}
struct const_container{ const const_item items[10]; };
void test_const_container() { const_container x;}
$ g++ -c gccxmlml.cxx
gccxmlml.cxx: In function 'void test_const_item()':
gccxmlml.cxx:2: error: structure 'x' with uninitialized const members
gccxmlml.cxx: In function 'void test_const_container()':
gccxmlml.cxx:4: error: structure 'x' with uninitialized const members
I think the class should have default constructor.
GCC disagrees, and for a good reason. The standard states that an
implicitly implemented default constructor will make the program
ill-formed if a user provided default constructor with empty initializer
list and empty body would make the program ill-formed. As you probably
know a const member _has_ to be initialized during construction, it must
be part of the constructor's initializer list:
$ cat gccxmlml1.cxx
struct Go {const int i; Go(): i(42) {} };
struct NoGo {const int i; NoGo() {} };
$ g++ -c gccxmlml1.cxx
gccxmlml1.cxx: In constructor 'NoGo::NoGo()':
gccxmlml1.cxx:2: error: uninitialized member 'NoGo::i' with 'const' type
'const int'
For obvious reasons (but check the standard 12.8.7 if you want to see
the proof) this restriction does not exist for the copy constructor.
Summary: I believe the standard forbids the default constructor that you
want to see, and that GCCXML with Brad's patch generates the proper
constructors and assignment operators.
Axel is correct according to C++98 12.1/7, and the recent patch detects
this case. Its attempt to synthesize these methods fails with the
errors above (but I suppress the messages). You can confirm this by
running gccxml with "-fpermissive" to prevent the synthesization test
from failing for these methods.
-Brad
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