[Bug debug/49407] New: unusable debuginfo for dll-imported functions.

[pluto at agmk dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49407

           Summary: unusable debuginfo for dll-imported functions.
           Product: gcc
           Version: 4.6.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: pl...@agmk.net


Hi,

i;m currently testing the 4,6-based i686-pc-mingw32 toolchain and
afaics the debuginfo for dll-imported functions are quite unusable :/

$ cat d.cpp
#include <stdio.h>
extern "C" __declspec(dllexport) void bar( void )
{
        puts( "bar is here!" );
}

$ cat m.cpp
#include <stdio.h>
extern "C" void bar( void );
int main()
{
        bar();
}

$ make
/local/devel/toolchain46/i686-pc-mingw32/bin/i686-pc-mingw32-g++ -Wall
-mthreads -g2 d.cpp -shared -o d.dll
/local/devel/toolchain46/i686-pc-mingw32/bin/i686-pc-mingw32-objdump -xw d.dll
> d.txt
/local/devel/toolchain46/i686-pc-mingw32/bin/i686-pc-mingw32-g++ -Wall
-mthreads -g2 m.cpp -o m.exe d.dll
/local/devel/toolchain46/i686-pc-mingw32/bin/i686-pc-mingw32-objdump -xw m.exe
> m.txt

and now on windows host the gdb.exe shows me:

D:\mingw.tests>d:\mingw32\bin\gdb.exe m.exe
GNU gdb (GDB) 7.2.90.20110602-cvs
(...)
(gdb) b bar
Breakpoint 1 at 0x402798
(gdb) r
Starting program: D:\mingw.tests/m.exe
(...)
Breakpoint 1, 0x00402798 in bar ()
(gdb) disassemble
Dump of assembler code for function bar:
=> 0x00402798 <+0>:     jmp    *0x406200
   0x0040279e <+6>:     nop
   0x0040279f <+7>:     nop
End of assembler dump.
(gdb) si
0x6b4414c0 in ?? ()
(gdb) disassemble
No function contains program counter for selected frame.

at this point i can't debug the 'bar' function :(