CC: does not list "allocate", a member function of std::allocator.

[edison]

As the screenshots show, the allocate() of alloc is missing here:

[edison]

I did try with the ClangLib. It works, the allocate member function is list up:

but ClangLib is slow and not stable...

here is a test example with source code: http://en.cppreference.com/w/cpp/memory/allocator

[ollydbg]

Hi, edison, as you may already see that parsing C++ is not a very simple job, our buildin parser in C::B has many issues here and there especially handling templates, as you reported, this is a bug, but solving those issue are not quite easy as I can see. Unless you use some compiler's help (such as clang or maybe GCC).

[ollydbg]

BTW: can you make a minimal sample code, so that I can test this bug in my computer? Thanks.

[edison]

Code Select Expand

#include <memory>

int main()
{
    std::allocator<int> a1; // default allocator for ints
    // int * a = a1.allocate(10); // space for 10 ints

    int * a = a1. //<--- here is the bug happened.

    return 0;
}


[ollydbg]

Code Select Expand

#include <memory>

int main()
{
    std::allocator<int> a1; // default allocator for ints
    // int * a = a1.allocate(10); // space for 10 ints

    int * a = a1. //<--- here is the bug happened.

    return 0;
}


OK, I see the reason. (tested under MinGW 4.7.x compiler)

1, I see that std::allocator class is correctly located in
mingw-builds\473\mingw32\lib\gcc\i686-w64-mingw32\4.7.3\include\c++\bits\allocator.h around line 84

Code Select Expand


  /**
   * @brief  The @a standard allocator, as per [20.4].
   *
   *  See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt04ch11.html
   *  for further details.
   */
  template<typename _Tp>
    class allocator: public __glibcxx_base_allocator<_Tp>
    {
   public:
      typedef size_t     size_type;
      typedef ptrdiff_t  difference_type;
      typedef _Tp*       pointer;
      typedef const _Tp* const_pointer;
      typedef _Tp&       reference;
      typedef const _Tp& const_reference;
      typedef _Tp        value_type;

      template<typename _Tp1>
        struct rebind
        { typedef allocator<_Tp1> other; };

      allocator() throw() { }

      allocator(const allocator& __a) throw()
      : __glibcxx_base_allocator<_Tp>(__a) { }

      template<typename _Tp1>
        allocator(const allocator<_Tp1>&) throw() { }

      ~allocator() throw() { }

      // Inherit everything else.
    };



Look, there is not member named "allocate", so it should be in its base class. But when I hover the "__glibcxx_base_allocator", I can't see the declaration...

In mingw-builds\473\mingw32\lib\gcc\i686-w64-mingw32\4.7.3\include\c++\i686-w64-mingw32\bits\c++allocator.h
I see

Code Select Expand


#ifndef _GLIBCXX_CXX_ALLOCATOR_H
#define _GLIBCXX_CXX_ALLOCATOR_H 1

// Define new_allocator as the base class to std::allocator.
#include <ext/new_allocator.h>
#define __glibcxx_base_allocator  __gnu_cxx::new_allocator

#endif


and in mingw-builds\473\mingw32\lib\gcc\i686-w64-mingw32\4.7.3\include\c++\ext\new_allocator.h
I see

Code Select Expand


  template<typename _Tp>
    class new_allocator
    {
    public:
      typedef size_t     size_type;
      typedef ptrdiff_t  difference_type;
      typedef _Tp*       pointer;
      typedef const _Tp* const_pointer;
      typedef _Tp&       reference;
      typedef const _Tp& const_reference;
      typedef _Tp        value_type;

      template<typename _Tp1>
        struct rebind
        { typedef new_allocator<_Tp1> other; };

      new_allocator() _GLIBCXX_USE_NOEXCEPT { }

      new_allocator(const new_allocator&) _GLIBCXX_USE_NOEXCEPT { }

      template<typename _Tp1>
        new_allocator(const new_allocator<_Tp1>&) _GLIBCXX_USE_NOEXCEPT { }

      ~new_allocator() _GLIBCXX_USE_NOEXCEPT { }

      pointer
      address(reference __x) const _GLIBCXX_NOEXCEPT
      { return std::__addressof(__x); }

      const_pointer
      address(const_reference __x) const _GLIBCXX_NOEXCEPT
      { return std::__addressof(__x); }

      // NB: __n is permitted to be 0.  The C++ standard says nothing
      // about what the return value is when __n == 0.
      pointer
      allocate(size_type __n, const void* = 0)
      {
if (__n > this->max_size())
  std::__throw_bad_alloc();

return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp)));
      }


See the last function, it is there.

But I'm still not sure how to fix this bug in our CC's code.

[ollydbg]

Oh, it looks like it works OK here, see the screen shot.



I just close and reopen the project.

[edison]

I am using mingw-w64 4.2 i686 dw2 (gcc 4.9.1) and codeblocks svn 9904, close then re-open project does not help here.
I will try the CB 13.12 w/tdm-gcc 4.7.1 latter.

[ollydbg]

I am using mingw-w64 4.2 i686 dw2 (gcc 4.9.1) and codeblocks svn 9904, close then re-open project does not help here.
I will try the CB 13.12 w/tdm-gcc 4.7.1 latter.

My testing environment is latest C::B trunk and mingw-build 4.7.3.

[Jenna]

Works out of the box with C::B 9884 and "g++ (GCC) 4.8.3 20140624 (Red Hat 4.8.3-1)" 64Bit on Fedora 20.

[edison]

There is not change here when using CB 13.12 and TDM-GCC 4.7.1.

I will try SVN 9906 + TDM-GCC 4.8.1 latter.

[edison]

I think I have found out what cause this problem

when I use the fresh built SVN 9906, all works fine.

but when I trans the old GCC compiler to the new CB default.conf, the problem appear again.

here is the old .conf which seems cause this problem.

[edison]

When I enable the -std=c++11 in Compiler settings, then close the project and re-open the project, the problem appear again. @_@

update:
I had did some double check test, now I can confirm when enabled the -std=c++11(and -std=gnu++11 ) setting (in project's build option or cb's compiler settings ) will cause "allocate()" of allocator not show in the list.

why the gcc compiler switch affect the CC @_@ It's strange...

[Jenna]

When I enable the -std=c++11 in Compiler settings, then close the project and re-open the project, the problem appear again. @_@

update:
I had did some double check test, now I can confirm when enabled the -std=c++11(and -std=gnu++11 ) setting (in project's build option or cb's compiler settings ) will cause "allocate()" of allocator not show in the list.

Still works here, egally where I add the flags (in project or globally).

[edison]

Still works here, egally where I add the flags (in project or globally).

When I set the flag, close CB and re-run CB, then open the project, the allocate() of CC does not work.

My Ubuntu had something wrong, I will try it latter.

update:
When my project use Clang as compiler, the allocate() CC works even -std=c++11 option was checked.