[gcc-3.0 bug?] C++ symbols treated as C

[gcc-3.0 bug?] C++ symbols treated as C

[Andrey Slepuhin]

Hi,

Trying to upgrade from 20010311 to 20010419 gcc snapshot
(taken from CodeSourcery) I got undefined references
when linking my C++ code. Looking into assembler output I see the
things like following:

        movl    _ZN5grace16shared_allocatorE, %eax
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        movl    (%eax), %ecx
        pushl   $16
        pushl   %eax
.LCFI4:
        call    *8(%ecx)
        movl    %eax, %ebx
        addl    $16, %esp
        testl   %ebx, %ebx
        jne     .L3
        subl    $12, %esp
        pushl   $132
        pushl   $.LC0
        pushl   $_ZZN5grace5T_ValIiEnwEjE19__PRETTY_FUNCTION__
        pushl   $.LC1
        pushl   stderr
.LCFI5:
        call    fprintf
        addl    $20, %esp
        pushl   $.LC2
.LCFI6:
        call    _ZN3pxx5fatalEPcz
        addl    $16, %esp
.L3:
.LBE4:
.LBE3:
.LEHB5:
        subl    $10, %esp
        pushw   $0
        pushl   %ebx
        call    _ZN5grace5T_ValIiEC1Eb
.LEHE5:
        addl    $16, %esp
        .stabs  "test.cc",132,0,0,.Ltext2
.Ltext2:
        .stabn 68,0,13,.LM3-_Z5tmainiPPc
.LM3:
        xorl    %eax, %eax
        movl    -4(%ebp), %ebx
        leave
        ret
.LBE2:
        .p2align 2
.L5:
.LEHB13:
        movb    $1, %dl
        testb   %dl, %dl
        je      .L7
        .stabs  "../src/gr_tval.hh",132,0,0,.Ltext3
.Ltext3:
        .stabn 68,0,135,.LM4-_Z5tmainiPPc
.LM4:
        subl    $8, %esp
        movl    shared_allocator, %eax
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        movl    (%eax), %ecx
        pushl   %ebx
        pushl   %eax
        call    *12(%ecx)
        addl    $16, %esp
.L7:
        subl    $12, %esp
        pushl   $.LRTH5
        call    __rethrow
        .p2align 2
.L13:
.LEHE13:
.LCFI7:
        call    _ZSt9terminatev



Note that in lower part of code symbol `shared_allocator' looks like
C symbol. 20010311 snapshot produces correct mangled C++ name in that
place. What may be wrong in this situation?

Appropriate C++ code looks like this:

#include "gr_shared_allocator.hh"

template <typename val_t>
class T_Val
{

.....

void* operator new (size_t _size) \
{
  void* p = shared_allocator->allocate(_size);
  if (p == null) FATAL("Memory allocation failed");
  return p;
}

......
};

int tmain (int argc, char* argv[])
{
  T_Val<int>* p = new T_Val<int>;
  return 0;
}

where template class T_Val has overloaded new() operator:

Yes, I'm 100% sure that all declarations are done in proper places.
If needed, I can send actual .ii output but it is rather large.

Regards,
Andrey.

-- 
A right thing should be simple (tm)

Re: [gcc-3.0 bug?] C++ symbols treated as C

[Andrey Slepuhin]

On Mon, Apr 23, 2001 at 09:34:15AM +0400, Andrey Slepuhin wrote:
> Hi,
> 
> Trying to upgrade from 20010311 to 20010419 gcc snapshot
> (taken from CodeSourcery) I got undefined references
> when linking my C++ code. Looking into assembler output I see the
> things like following:

[snip]

Ok, I found a test case which localizes a problem.
Compiling the following program with 20010422 snapshot:

-------------------------------------------------------
#include <cstdio>

namespace A
{

int abcdef;

template <typename val_t>
class X
{
public:
  inline X ()
  {
    extern int abcdef;
    printf("%d\n", abcdef);
  }
};

}

using namespace A;

int main (int argc, char* argv[])
{
  X<int> x;
  return 0;
}
------------------------------------------------------------

I got the following error:
/tmp/ccWmhmdS.o: In function `A::X<int>::X()':
/tmp/ccWmhmdS.o(.gnu.linkonce.t._ZN1A1XIiEC1Ev+0xb): undefined reference to
`abcdef'
collect2: ld returned 1 exit status

Assembler output shows that "extern int abcdef;" is not considered as a member
of namespace A. 20010311 snapshot compiles this program without errors.
Making X non-template class also removes errors.

Regards,
Andrey.

-- 
A right thing should be simple (tm)