[avr-gcc-list] Duplicated C++ constructor code

[Greg Tunnock]

Hi,

I'm using avr-gcc-3.3.2002.10.01 on FreeBSD to compile C++ code. The listing
file from avr-objdump show that the compile has duplicated the code for the
class constructors.

Here is a simple C++ source file that shows the problem:
  #include <avr/io.h>

  #if defined(__AVR_AT90S2313__)
  #define LED1 PD4
  #elif defined(__AVR_ATmega128__)
  #define LED1 DD4
  #endif

  class Led1
  {
  public:
    Led1();
    void off();
    void on();

  private:
    Led1(const Led1 &from);                      // Prevent copying.
    Led1 &operator=(const Led1 &from);           // Prevent assignment.
  };

  Led1::Led1()
  {
    sbi(DDRD, LED1);
  }

  void Led1::off()
  {
    sbi(PORTD, LED1);
  }

  void Led1::on()
  {
    cbi(PORTD, LED1);
  }

  int main()
  {
    Led1 led1;

    for (;;)
    {
      led1.off();
      led1.on();
    }
  }

And the sections of the listing that shows the duplicated constructor code
for Led1:

  000000ca g     F .text        00000004 Led1::Led1()
  000000ce g     F .text        00000004 Led1::Led1()

  000000ca <Led1::Led1()>:
  };

  Led1::Led1()
  {
    sbi(DDRD, LED1);
    ca: 8c 9a           sbi     0x11, 4 ; 17
  }
    cc: 08 95           ret

  000000ce <Led1::Led1()>:
    ce: 8c 9a           sbi     0x11, 4 ; 17
    d0: 08 95           ret

The commands lines that the C++ source file is compiled with and the listing
file generated with are:

  avr-g++ -g -Wall -O2 -mmcu=atmega128 -fno-exceptions -c -o main.o main.cc
  avr-g++ -g -Wall -O2 -mmcu=atmega128 -Wl,-Map,main.map -o main.elf main.o
  avr-objdump -h -S -C -D -w -a -t -f main.elf > main.lst

When stepping through code with avr-gdb on simulavr, only the second
constructor (000000ce) is called.

Is this a problem with avr-gcc? Or am I doing something silly? Or have I
miss understood some aspect of C++?

Cheers,
Greg Tunnock

avr-gcc-list at http://avr1.org