Re: Building GDB 7.3.92 with MinGW

[asmwarrior <asmwarrior@gmail.com>]

On 2012-1-12 1:48, Doug Evans wrote:
> On Tue, Jan 10, 2012 at 4:35 PM, asmwarrior<asmwarrior@gmail.com>  wrote:
>> On 2012-1-11 5:23, Doug Evans wrote:
>>> For one, remembering to pass -data-directory is a pain.
>>
>> This parameter does not work correctly under MinGW in the case that I would
>> like gdb to automatically run the python script when it startup.
> When you say "run the python script", *which* python script are you
> referring to?
The script code is embedded in c source code in "python.c", in function: voidfinish_python_initialization (void)
>
>> Normally, my gdb is put in MinGW/bin, and the gdb's own python script is
>> under:
>> MinGW\share\gdb\python\gdb\*.py
>>
>> I need to hard-code the code in gdb/main.c to set the data-directory value.
>> (Because gdb is build from MSYS+MinGW, but it run normally on Windows shell
>> without MSYS)
>>
>> Here are some hard-code modify to the main.c file, if you do not change
>> this, there is no way to load gdb's own python scripts.
>>
>> diff --git a/gdb/main.c b/gdb/main.c
>> index 8b45c25..46b11a8 100644
>> --- a/gdb/main.c
>> +++ b/gdb/main.c
>> @@ -42,6 +42,10 @@
>>   #include "python/python.h"
>>   #include "objfiles.h"
>>   +#ifdef _WIN32
>> +extern int get_app_fullpath(char *location, int length);
>> +#endif
>> +
>>   /* The selected interpreter.  This will be used as a set command
>>     variable, so it should always be malloc'ed - since
>>     do_setshow_command will free it.  */
>> @@ -355,8 +359,27 @@ captured_main (void *data)
>>    debug_file_directory = relocate_gdb_directory (DEBUGDIR,
>>                                                  DEBUGDIR_RELOCATABLE);
>>   +
>> +#ifdef _WIN32
>> +  {
>> +    char location[500];
>> +    int len= get_app_fullpath(location, sizeof (location));
>> +    if (len == 0 || len>  500 - 1)
>> +      gdb_datadir = relocate_gdb_directory
>> (GDB_DATADIR,GDB_DATADIR_RELOCATABLE);
>> +    else
>> +    {
>> +        char *p_slash =strrchr(location,'\\');
>> +        *p_slash = '\000';
>> +        p_slash =strrchr(location,'\\'); /* remove the bin folder*/
>> +        *p_slash = '\000';
>> +        strcat(location,"\\share\\gdb");
>> +        gdb_datadir = xstrdup (location);
>> +    }
>> +  }
>> +#else
>>    gdb_datadir = relocate_gdb_directory (GDB_DATADIR,
>> -                                       GDB_DATADIR_RELOCATABLE);
>> +                                       GDB_DATADIR_RELOCATABLE);
>> +#endif
>>   #ifdef WITH_PYTHON_PATH
>>    {
>>
>> If I remember correctly, I have post it some months ago.
> *If* there is a bug here, and it's not pilot error, it feels like
> perhaps the bug is in relocate_gdb_directory.
> [Why don't all calls to relocate_gdb_directory require similar treatment?
> Thus this feels like the wrong way to go.]
>
> Maybe if you provide a sample session (and complete session please, no
> editing to trim it down), that will help.
I have just look at my notes half years ago(no time to write a complete session right now), the issue is:
In the file:

build\gdb\config.status

The value is hard-coded:

D["DEBUGDIR"]=" \"/mingw/lib/debug\""
D["DEBUGDIR_RELOCATABLE"]=" 1"
D["GDB_DATADIR"]=" \"/mingw/share/gdb\""

There are some code snippet:

gdb_program_name = xstrdup (argv[0]);

  if (! getcwd (gdb_dirbuf, sizeof (gdb_dirbuf)))
     /* Don't use *_filtered or warning() (which relies on
       current_target) until after initialize_all_files().  */
     fprintf_unfiltered (gdb_stderr,
            _("%s: warning: error finding "
              "working directory: %s\n"),
                        argv[0], safe_strerror (errno));

  current_directory = gdb_dirbuf;

  /* Set the sysroot path.  */
  gdb_sysroot = relocate_gdb_directory (TARGET_SYSTEM_ROOT,
                    TARGET_SYSTEM_ROOT_RELOCATABLE);

  debug_file_directory = relocate_gdb_directory (DEBUGDIR,
                         DEBUGDIR_RELOCATABLE);

  gdb_datadir = relocate_gdb_directory (GDB_DATADIR,
                    GDB_DATADIR_RELOCATABLE);

But those values were not set correctly, so I need to hack the path under MinGW.

It is quite simple to test whether GDB set the python path correctly, just run:

python print gdb.PYTHONDIR

If it shows the correct path, then it's good.

PS: I will have a travel in two days, so further response from me will be some bit later.

asmwarrior
ollydbg from codeblocks' forum