Re: Path handling bug in GDB included with MingW 3.1.0-1

[Chris Johns <cjohns at cybertec dot com dot au>]

Eli Zaretskii wrote:
> > From: "Michael Stather" <michaelstather@nuzi.de>
> > Date: Sun, 5 Oct 2003 23:48:35 +0200
> >
> > g++ -g -o p.exe c:/p/p.cpp -mwindows
> > gdb
> > break "c:/p/p.cpp:7"
> > Run
> >
> > gdb won?t stop at the breakpoint.
> > however if I do:
> >
> > cd c:\m

Not sure if this is suppose to be 'm' or 'p' and if this makes a difference.

> > g++ -g -o p.exe p.cpp -mwindows
> > gdb
> > break "p.cpp:7"
> > run
> >
> > it breaks correctly.
>
>
> Sounds like the MinGW port isn't writing leading directories of the
> files into the debug info.

The 5.2.1-1 patch for MinGW stripped a leading '/' from a path for some 
reason.

> Questions:
>
> What is the default debug info format used by the MinGW port of GCC?

stabs

> Does it help to use -gstabs+ instead of just -g?

No change the trace below.

> Do you see the leading directories of the source file names if you
> run "objdump --debug" on the object files?

I tried the 20030930 snapshot with a new MinGW patch the other day and I 
could set the break point and gdb stopped. I posted this result to the 
MinGW mailing list.

I decided to try gdb 6.0. This is what I have found with a simple hello 
world compiled with:

 > g++ -g -o p p.cpp -mwindows

and gdb run in a cmd box on XP:

 (gdb) info files
 Symbols from "C:\p/p.exe".
 Local exec file:
         `C:\p/p.exe', file type pei-i386.
         Entry point: 0x401000
         0x00401000 - 0x00433300 is .text
         0x00434000 - 0x00435234 is .data
         0x00436000 - 0x0043a9e0 is .bss
         0x0043b000 - 0x0043b7f4 is .idata
 (gdb) b "c:\p/p.cpp:6"
 Internal: readin p.cpp pst for `c:\p/p.cpp' found when no symtab found.
 (gdb) b "c:/p/p.cpp:6"
 Breakpoint 1 at 0x4012da: file p.cpp, line 6.
 (gdb) b "c:\p\p.cpp:6"
 No source file named c:\p\p.cpp.
 (gdb) b "p.cpp:6"
 Note: breakpoint 1 also set at pc 0x4012da.
 Breakpoint 2 at 0x4012da: file p.cpp, line 6.
 (gdb) maintenance info symtabs
 { objfile C:\p/p.exe ((struct objfile *) 010EFB00)
   { symtab p.cpp ((struct symtab *) 011A1D00)
     dirname C:/p/
     fullname C:/p/p.cpp
     blockvector ((struct blockvector *) 01193D10) (primary)
     debugformat stabs
   }
  [snip]

The MinGW patch I used is on SF under the MinGW project. It contains no 
changes to the source file or symbol handling in GDB.

--
 Chris Johns, cjohns at cybertec.com.au