Hi,

I was testing the new connector to MSSQL when I found a problem. If I compile and run in console, I have no memleak. Good. But if I put a breakpoint in AConnection.Free; and press F8, I got this:

ERROR
,msg="Warning:\nCannot insert breakpoint -237.\nError accessing memory address 0x7816cd30: Input/output error.\n"

I don't know if this problem happen just in new connector. I don't have others DBMS installed here, justo MSSQLServer so, could you test using another class to connect in other DBMS?

The code below is very simple (see http://wiki.freepascal.org/SqlDBHowto). -------------------------------------------------------------------------------- program t1;

{$mode objfpc}{$H+}

uses
heaptrc,
Classes, SysUtils, DB, sqldb,
mssqlconn; << change

var
  AConnection : TSQLConnection;
Procedure CreateConnection;
begin
  AConnection := TMSSQLConnection.Create(nil);  << change
  AConnection.Hostname := 'localhost';
  AConnection.DatabaseName := 'database';
  AConnection.UserName := 'user';
  AConnection.Password := '**********';
end;
begin
  CreateConnection;
  AConnection.Open;
  if Aconnection.Connected then
    writeln('Succesful connect!')
  else
    writeln('Error');
  AConnection.Close;
  AConnection.Free;  << breakpoint here
  writeln('done');
end.

My ENV is:
Lazarus 0.9.31 r36175 FPC 2.6.1 i386-win32-win32/win64

FPC
URL: http://svn.freepascal.org/svn/fpc/branches/fixes_2_6 Repository Root: http://svn.freepascal.org/svn/fpc Repository UUID: 3ad0048d-3df7-0310-abae-a5850022a9f2 Revision: 20521
Node Kind: directory
Schedule: normal
Last Changed Author: marco
Last Changed Rev: 20519
Last Changed Date: 2012-03-15 09:18:24 -0300 (Thu, 15 Mar 2012)

GDB
URL: http://svn.freepascal.org/svn/lazarus/binaries Repository Root: http://svn.freepascal.org/svn/lazarus Repository UUID: 4005530d-fff6-0310-9dd1-cebe43e6787f Revision: 36176
Node Kind: directory
Schedule: normal
Last Changed Author: martin
Last Changed Rev: 32524
Last Changed Date: 2011-09-27 13:23:25 -0300 (Tue, 27 Sep 2011) --------------------------------------------------------------------------------

Thanks,
Marcos Douglas

A negative breakpoint means internal to gdb (like a breakpoint gdb sets for stepping). So when you press F8 gdb apparently can't get the correct location where the step should end.

Are you sure your app (and package that has debug info) are compiled:
- with either -O0 or -O1 (no other optimization enabled)
- your app is NOT smartlinked

wiki.lazarus.freepascal.org/GDB_Debugger_Tips

I compile FPC using these options: UPXPROG=echo COPYTREE=echo OPT="-gl" My applications, in debbuger mode, always use -O1 option. I use smartlinked option just for release.

Marcos Douglas

Tem umas opções com o novo GDB >6.5 que parece ser a melhor opção. Vou recompilar o FPC e Lazarus utilizando:
-gl -gw -godwarfsets

Marcos Douglas

Martin,
I recompiled FPC and Lazarus using -gl -gw2 -godwarfsets options, but the problem continues.

Marcos Douglas
PS: Guys, sorry about my mail before. It would be for other list, in Portuguese.

I don't know where/why it upsets gdb.

The above will allow you to step into RTL/packages.

It certainly is no error in the app, but a problem in the debug info (or what gdb makes of it).

There are 3 possibilities:
1) FPC writes bad debug info. You can try -gs versus -gw (stabs/dwarf).
2) The linker gets it wrong. Try -Xe
3) gdb is buggy. Which version are you on?

Do all lines get a blue dot? (except maybe "else" and empty lines)

-----------
Where to get mssqlcon ?

----
As workarounds:
1) Try setting a breakpoint on next command and use F9
2) Single step in assembler window (single step asm instructions)

Did you try to continue, after the error (if you are lucky, it might be possible)?

--------
For 64 bit, latest gdb (I have not tested it yet)

http://sourceforge.net/projects/mingw-w64/files/Toolchains%20targetting%20Win64/Personal%20Builds/rubenvb/4.7.0-3/x86_64-w64-mingw32-gcc-4.7.0-3_rubenvb.7z/download

I use gdb 7.3 (http://svn.freepascal.org/svn/lazarus/binaries/) only in 32 bit.

Do all lines get a blue dot? (except maybe "else" and empty lines)

Definitely yes.

----------- Where to get mssqlcon ? ----

In trunk http://svn.freepascal.org/svn/fpc/trunk/packages/fcl-db/src/sqldb/mssql/ But I had these sources because I tested for LacaK before merged in FPC sources.

As workarounds: 1) Try setting a breakpoint on next command and use F9 2) Single step in assembler window (single step asm instructions)

if I use F9 this problem does not occur.

Did you try to continue, after the error (if you are lucky, it might be possible)?

Yes, I tried.
No is possible to continue and the negative number is going incrementing two by two.

I only use 32 bit.

Marcos Douglas

For any kind of stepping yes.

But does F9 run?
e.g. set your own next breakpoint, and use F9

Or try asm steps

---
Both F8 and F7 mean the debugger must work out the address of the next statement (or list of possible next statements)

It seems the debugger gets this address wrong, and therefore it can not set the breakpoint.
Breakpoint numbers are not re-used. So that is why each time you see a new number.

Positive numbers: breakpoints set by you
Negative: breakpoints internally used by GDB

Marcos Douglas wrote

I compile FPC using these options: UPXPROG=echo COPYTREE=echo OPT="- gl"

You should use OPT="-O- -gl" if you want to debug standard FPC units. The default for building the entire FPC source tree is -O2. Optimizations generally have little effect on the line number information though.

Jonas

Interesting. 0x7816cd30

I usually get addresses around 0x0400000 for 32 bit. It can be changed by config. But if you have not... Check witth the disassembler where the rest of your code is.

Maybe that address is in a DLL or kernel? It still wouldn't explain why gdb would try to set a break there, but maybe why it can not.

If I have 2 breakpoint:
Stop on the first... F9;
Stop on the second... F9..... no errors.

But, in the second, if I use F8.... error.

Anyway, thanks for the GDB tips.

Marcos Douglas

Before I used OPT="-gl" and I already debug FPC units. I recompiled using OPT="-gl -gw2 -godwarfsets" after read this link: wiki.lazarus.freepascal.org/GDB_Debugger_Tips

The OPT="-O- -gl" options are better?

Marcos Douglas

Well, SQLdb uses a DLL to connect. Perhaps a clue? Although some friends also tested using others drivers and got the same problem.

Marcos Douglas

Does the issue happen the first time you press F8, or to you have to press a 2nd time?

In other words: Is it possble the debugger pauses inside free (possible in a dll) and that when you hit F8 then, it can not step, because the dll has no debug info?

If in stopped in the DLL, it might still put the green arrow on your source => first stack with frame debug info...

Open and watch the stack window.

---
Also open the "debug output" window. Open this one before you start your app. Then copy the content.

---
If indeed gdb stops inside a dll, then F8 simply can not work

You should at least add the "-O-" to your OPT argument, because this way the optimizations are switched off which might(!) cause your debug problems.

Regards,
Sven

When I press a first time... but I think some times in a 2nd time. =|

In other words: Is it possble the debugger pauses inside free (possible in a dll) and that when you hit F8 then, it can not step, because the dll has no debug info?

Yes, I think is possible...

The content was copied below.

--- If indeed gdb stops inside a dll, then F8 simply can not work

====================================================

<-file-exec-and-symbols "W:/md/dev/freepascal/lib/gh/bin/dbtest.exe"> ^done
(gdb)
<-gdb-set language pascal>
^done
(gdb)
<-environment-cd .>
^done
(gdb)
<-environment-cd "W:/md/dev/freepascal/lib/gh/bin/"> ^done
(gdb)
<-data-evaluate-expression FPC_THREADVAR_RELOCATE_PROC> ^done,value="0x0"
(gdb)
<-exec-arguments >
^done
(gdb)
<-gdb-set language pascal>
^done
(gdb)
<ptype TObject>
&"ptype TObject\n"
~"type = TOBJECT = class \n"
~" public\n"
~" constructor CREATE (TOBJECT, POINTER) : TOBJECT;\n" ~" destructor ~DESTROY (TOBJECT, POINTER); virtual;\n" ~" function NEWINSTANCE (unnamedtype) : TOBJECT; virtual;\n" ~" procedure FREEINSTANCE (TOBJECT); virtual;\n" ~" function SAFECALLEXCEPTION (TOBJECT, TOBJECT, POINTER) : HRESULT; virtual;\n"
~" procedure DEFAULTHANDLER (TOBJECT, var); virtual;\n" ~" procedure FREE (TOBJECT);\n"
~" function INITINSTANCE (unnamedtype, POINTER) : TOBJECT;\n" ~" procedure CLEANUPINSTANCE (TOBJECT);\n"
~" function CLASSTYPE (unnamedtype) : TCLASS;\n" ~" function CLASSINFO (unnamedtype) : POINTER;\n" ~" function CLASSNAME (unnamedtype, SHORTSTRING) : SHORTSTRING;\n" ~" function CLASSNAMEIS (unnamedtype, SHORTSTRING) : BOOLEAN;\n" ~" function CLASSPARENT (unnamedtype) : TCLASS;\n" ~" function INSTANCESIZE (unnamedtype) : LONGINT;\n" ~" function INHERITSFROM (unnamedtype, TCLASS) : BOOLEAN;\n" ~" function STRINGMESSAGETABLE (unnamedtype) : PSTRINGMESSAGETABLE;\n" ~" function METHODADDRESS (unnamedtype, SHORTSTRING) : POINTER;\n" ~" function METHODNAME (unnamedtype, POINTER, SHORTSTRING) : SHORTSTRING;\n" ~" function FIELDADDRESS (TOBJECT, SHORTSTRING) : POINTER;\n" ~" procedure AFTERCONSTRUCTION (TOBJECT); virtual;\n" ~" procedure BEFOREDESTRUCTION (TOBJECT); virtual;\n" ~" procedure DEFAULTHANDLERSTR (TOBJECT, var); virtual;\n" ~" procedure DISPATCH (TOBJECT, var); virtual;\n" ~" procedure DISPATCHSTR (TOBJECT, var); virtual;\n" ~" function GETINTERFACE (TOBJECT, TGUID, out) : BOOLEAN;\n" ~" function GETINTERFACEBYSTR (TOBJECT, SHORTSTRING, out) : BOOLEAN;\n" ~" function GETINTERFACEWEAK (TOBJECT, TGUID, out) : BOOLEAN;\n" ~" function GETINTERFACEENTRY (unnamedtype, TGUID) : PINTERFACEENTRY;\n" ~" function GETINTERFACEENTRYBYSTR (unnamedtype, SHORTSTRING) : PINTERFACEENTRY;\n"
~" function GETINTERFACETABLE (unnamedtype) : PINTERFACETABLE;\n" ~" function UNITNAME (unnamedtype, ANSISTRING) : ANSISTRING;\n" ~" function EQUALS (TOBJECT, TOBJECT) : BOOLEAN; virtual;\n" ~" function GETHASHCODE (TOBJECT) : LONGINT; virtual;\n" ~" function TOSTRING (TOBJECT, ANSISTRING) : ANSISTRING; virtual;\n" ~"end\n"
^done
(gdb)
<ptype Exception>
&"ptype Exception\n"
~"type = EXCEPTION = class : public TOBJECT \n"
~" private\n"
~" FMESSAGE : ANSISTRING;\n"
~" FHELPCONTEXT : LONGINT;\n"
~"\n"
~" public\n"
~" constructor CREATE (EXCEPTION, POINTER, ANSISTRING) : ^EXCEPTION;\n" ~" constructor CREATEFMT (EXCEPTION, POINTER, ANSISTRING, unnamedtype, LONGINT) : ^EXCEPTION;\n"
~" constructor CREATERES (EXCEPTION, POINTER, PSTRING) : ^EXCEPTION;\n" ~" constructor CREATERESFMT (EXCEPTION, POINTER, PSTRING, unnamedtype, LONGINT) : ^EXCEPTION;\n"
~" constructor CREATEHELP (EXCEPTION, POINTER, ANSISTRING, LONGINT) : ^EXCEPTION;\n"
~" constructor CREATEFMTHELP (EXCEPTION, POINTER, ANSISTRING, unnamedtype, LONGINT, LONGINT) : ^EXCEPTION;\n"
~" constructor CREATERESHELP (EXCEPTION, POINTER, PSTRING, LONGINT) : ^EXCEPTION;\n"
~" constructor CREATERESFMTHELP (EXCEPTION, POINTER, PSTRING, unnamedtype, LONGINT, LONGINT) : ^EXCEPTION;\n"
~"end\n"
^done
(gdb)
<ptype Shortstring>
&"ptype Shortstring\n"
~"type = SHORTSTRING = record \n"
~" length : BYTE;\n"
~" st : array [1..255] of CHAR;\n"
~"end\n"
^done
(gdb)
<ptype pointer>
&"ptype pointer\n"
~"type = ^POINTER\n"
^done
(gdb)
<ptype byte>
&"ptype byte\n"
~"type = BYTE\n"
^done
(gdb)
<info file>
&"info file\n"
~"Symbols from \"w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dbtest.exe\".\n" ~"Local exec file:\n"
~"\t`w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dbtest.exe', file type pei-i386.\n" ~"\tEntry point: 0x471e50\n"
~"\t0x00401000 - 0x00471e90 is .text\n"
~"\t0x00472000 - 0x0048abec is .data\n"
~"\t0x0048b000 - 0x0048fb94 is .bss\n"
~"\t0x00491000 - 0x00491b34 is .idata\n"
^done
(gdb)
<-data-evaluate-expression sizeof(POINTER)>
^done,value="4"
(gdb)
<-break-insert +0>
^done,bkpt={number="12",type="breakpoint",disp="keep",enabled="y",addr="0x004016d8",func="EXECSELECT",file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="28",times="0",original-location="dbtest.pas:28"} (gdb)
<-break-insert main>
^done,bkpt={number="13",type="breakpoint",disp="keep",enabled="y",addr="0x004017d1",func="main",file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="37",times="0",original-location="main"} (gdb)
<-break-insert *4660816>
^done,bkpt={number="14",type="breakpoint",disp="keep",enabled="y",addr="0x00471e50",func="_FPC_MAINCRTSTARTUP",file="sysinitpas.pp",fullname="w:\\md\\dev\\freepascal\\compiler\\2.6.1\\rtl\\win32\\sysinitpas.pp",line="30",times="0",original-location="*4660816"} (gdb)
<-exec-run>
=thread-group-started,id="i1",pid="4220"
=thread-created,id="1",group-id="i1"
~"[New Thread 4220.0xe88]\n"
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="C:\\WINDOWS\\system32\\ntdll.dll",target-name="C:\\WINDOWS\\system32\\ntdll.dll",host-name="C:\\WINDOWS\\system32\\ntdll.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\kernel32.dll",target-name="C:\\WINDOWS\\system32\\kernel32.dll",host-name="C:\\WINDOWS\\system32\\kernel32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\oleaut32.dll",target-name="C:\\WINDOWS\\system32\\oleaut32.dll",host-name="C:\\WINDOWS\\system32\\oleaut32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\advapi32.dll",target-name="C:\\WINDOWS\\system32\\advapi32.dll",host-name="C:\\WINDOWS\\system32\\advapi32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\rpcrt4.dll",target-name="C:\\WINDOWS\\system32\\rpcrt4.dll",host-name="C:\\WINDOWS\\system32\\rpcrt4.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\secur32.dll",target-name="C:\\WINDOWS\\system32\\secur32.dll",host-name="C:\\WINDOWS\\system32\\secur32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\gdi32.dll",target-name="C:\\WINDOWS\\system32\\gdi32.dll",host-name="C:\\WINDOWS\\system32\\gdi32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\user32.dll",target-name="C:\\WINDOWS\\system32\\user32.dll",host-name="C:\\WINDOWS\\system32\\user32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\msvcrt.dll",target-name="C:\\WINDOWS\\system32\\msvcrt.dll",host-name="C:\\WINDOWS\\system32\\msvcrt.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\ole32.dll",target-name="C:\\WINDOWS\\system32\\ole32.dll",host-name="C:\\WINDOWS\\system32\\ole32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\imm32.dll",target-name="C:\\WINDOWS\\system32\\imm32.dll",host-name="C:\\WINDOWS\\system32\\imm32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\lpk.dll",target-name="C:\\WINDOWS\\system32\\lpk.dll",host-name="C:\\WINDOWS\\system32\\lpk.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\usp10.dll",target-name="C:\\WINDOWS\\system32\\usp10.dll",host-name="C:\\WINDOWS\\system32\\usp10.dll",symbols-loaded="0",thread-group="i1" *stopped,reason="breakpoint-hit",disp="keep",bkptno="14",frame={addr="0x00471e50",func="_FPC_MAINCRTSTARTUP",args=[],file="sysinitpas.pp",fullname="w:\\md\\dev\\freepascal\\compiler\\2.6.1\\rtl\\win32\\sysinitpas.pp",line="30"},thread-id="1",stopped-threads="all" (gdb)
<-break-delete 13>
^done
(gdb)
<-break-delete 14>
^done
(gdb)
<-break-delete 12>
^done
(gdb)
<info program>
&"info program\n"
~"\tUsing the running image of child Thread 4220.0xe88.\n" ~"Program stopped at 0x471e50.\n"
~"It stopped at a breakpoint that has since been deleted.\n" ~"Type \"info stack\" or \"info registers\" for more information.\n" ^done
(gdb)
<info address FPC_RAISEEXCEPTION>
&"info address FPC_RAISEEXCEPTION\n"
~"Symbol \"FPC_RAISEEXCEPTION\" is at 0x40b070 in a file compiled without debugging.\n"
^done
(gdb)
<-break-insert *4239472>
^done,bkpt={number="15",type="breakpoint",disp="keep",enabled="y",addr="0x0040b070",func="fpc_raiseexception",file="W:/md/dev/freepascal/compiler/2.6.1/rtl/inc/except.inc",fullname="w:\\md\\dev\\freepascal\\compiler\\2.6.1\\rtl\\inc\\except.inc",line="191",times="0",original-location="*4239472"} (gdb)
<info address FPC_BREAK_ERROR>
&"info address FPC_BREAK_ERROR\n"
~"Symbol \"FPC_BREAK_ERROR\" is at 0x40cef0 in a file compiled without debugging.\n"
^done
(gdb)
<-break-insert *4247280>
^done,bkpt={number="16",type="breakpoint",disp="keep",enabled="y",addr="0x0040cef0",func="HANDLEERRORADDRFRAME",file="W:/md/dev/freepascal/compiler/2.6.1/rtl/inc/system.inc",fullname="w:\\md\\dev\\freepascal\\compiler\\2.6.1\\rtl\\inc\\system.inc",line="962",times="0",original-location="*4247280"} (gdb)
<info address FPC_RUNERROR>
&"info address FPC_RUNERROR\n"
~"Symbol \"FPC_RUNERROR\" is at 0x40cfe0 in a file compiled without debugging.\n"
^done
(gdb)
<-break-insert *4247520>
^done,bkpt={number="17",type="breakpoint",disp="keep",enabled="y",addr="0x0040cfe0",func="RUNERROR",file="W:/md/dev/freepascal/compiler/2.6.1/rtl/inc/system.inc",fullname="w:\\md\\dev\\freepascal\\compiler\\2.6.1\\rtl\\inc\\system.inc",line="1007",times="0",original-location="*4247520"} (gdb)
<-symbol-list-lines W:\md\dev\freepascal\lib\gh\examples\db\mssql\dbtest.pas> ^done,lines=[{pc="0x00401640",line="21"},{pc="0x0040164c",line="21"},{pc="0x00401678",line="22"},{pc="0x0040167f",line="23"},{pc="0x0040169d",line="24"},{pc="0x004016bb",line="25"},{pc="0x004016d0",line="26"},{pc="0x004016d8",line="28"},{pc="0x0040174b",line="29"},{pc="0x00401769",line="32"},{pc="0x00401785",line="34"},{pc="0x004017ad",line="34"},{pc="0x004017c0",line="36"},{pc="0x004017d1",line="37"},{pc="0x004017e8",line="38"},{pc="0x004017ff",line="39"},{pc="0x0040181d",line="41"},{pc="0x0040182c",line="45"},{pc="0x00401842",line="46"},{pc="0x00401858",line="47"},{pc="0x0040186e",line="48"},{pc="0x00401884",line="49"},{pc="0x0040188e",line="50"},{pc="0x004018b7",line="53"},{pc="0x004018c1",line="54"},{pc="0x004018c9",line="58"},{pc="0x004018df",line="59"},{pc="0x004018ef",line="60"},{pc="0x00401918",line="63"},{pc="0x00401922",line="64"},{pc="0x00401940",line="65"},{pc="0x00401960",line="66"},{pc="0x00401980",line="67"},{pc="0x004019a0",line="68"},{pc="0x004019c0",line="69"},{pc="0x004019d0",line="71"},{pc="0x004019f9",line="72"},{pc="0x004019fe",line="75"},{pc="0x00401a08",line="76"},{pc="0x00401a26",line="77"},{pc="0x00401a46",line="78"},{pc="0x00401a66",line="79"},{pc="0x00401a76",line="81"},{pc="0x00401a9f",line="82"},{pc="0x00401aa4",line="84"},{pc="0x00401ab4",line="86"},{pc="0x00401ad0",line="87"},{pc="0x00401aee",line="88"},{pc="0x00401b0e",line="89"},{pc="0x00401b2e",line="90"},{pc="0x00401b4e",line="91"},{pc="0x00401b6e",line="92"},{pc="0x00401b7d",line="94"},{pc="0x00401b96",line="97"},{pc="0x00401bbf",line="98"},{pc="0x00401bc4",line="113"},{pc="0x00401bce",line="114"},{pc="0x00401bec",line="115"},{pc="0x00401bfc",line="116"},{pc="0x00401c2a",line="118"},{pc="0x00401c34",line="119"},{pc="0x00401c4d",line="121"}] (gdb)
<info line "W:\md\dev\freepascal\lib\gh\examples\db\mssql\dbtest.pas":119> &"info line \"W:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas\":119\n" ~"Line 119 of \"dbtest.pas\" starts at address 0x401c34 <main+1140> and ends at 0x401c4d <main+1165>.\n"
^done
(gdb)
<-break-insert -f dbtest.pas:119>
^done,bkpt={number="18",type="breakpoint",disp="keep",enabled="y",addr="0x00401c34",func="main",file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="119",times="0",original-location="dbtest.pas:119"} (gdb)
<-break-enable 18>
^done
(gdb)
<-exec-continue>
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",target-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",host-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",target-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",host-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\shell32.dll",target-name="C:\\WINDOWS\\system32\\shell32.dll",host-name="C:\\WINDOWS\\system32\\shell32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\shlwapi.dll",target-name="C:\\WINDOWS\\system32\\shlwapi.dll",host-name="C:\\WINDOWS\\system32\\shlwapi.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",target-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",host-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\ws2_32.dll",target-name="C:\\WINDOWS\\system32\\ws2_32.dll",host-name="C:\\WINDOWS\\system32\\ws2_32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\ws2help.dll",target-name="C:\\WINDOWS\\system32\\ws2help.dll",host-name="C:\\WINDOWS\\system32\\ws2help.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",target-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",host-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\comctl32.dll",target-name="C:\\WINDOWS\\system32\\comctl32.dll",host-name="C:\\WINDOWS\\system32\\comctl32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\System32\\mswsock.dll",target-name="C:\\WINDOWS\\System32\\mswsock.dll",host-name="C:\\WINDOWS\\System32\\mswsock.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\dnsapi.dll",target-name="C:\\WINDOWS\\system32\\dnsapi.dll",host-name="C:\\WINDOWS\\system32\\dnsapi.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\iphlpapi.dll",target-name="C:\\WINDOWS\\system32\\iphlpapi.dll",host-name="C:\\WINDOWS\\system32\\iphlpapi.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\mprapi.dll",target-name="C:\\WINDOWS\\system32\\mprapi.dll",host-name="C:\\WINDOWS\\system32\\mprapi.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\activeds.dll",target-name="C:\\WINDOWS\\system32\\activeds.dll",host-name="C:\\WINDOWS\\system32\\activeds.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\adsldpc.dll",target-name="C:\\WINDOWS\\system32\\adsldpc.dll",host-name="C:\\WINDOWS\\system32\\adsldpc.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\netapi32.dll",target-name="C:\\WINDOWS\\system32\\netapi32.dll",host-name="C:\\WINDOWS\\system32\\netapi32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\wldap32.dll",target-name="C:\\WINDOWS\\system32\\wldap32.dll",host-name="C:\\WINDOWS\\system32\\wldap32.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\atl.dll",target-name="C:\\WINDOWS\\system32\\atl.dll",host-name="C:\\WINDOWS\\system32\\atl.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\rtutils.dll",target-name="C:\\WINDOWS\\system32\\rtutils.dll",host-name="C:\\WINDOWS\\system32\\rtutils.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\samlib.dll",target-name="C:\\WINDOWS\\system32\\samlib.dll",host-name="C:\\WINDOWS\\system32\\samlib.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\setupapi.dll",target-name="C:\\WINDOWS\\system32\\setupapi.dll",host-name="C:\\WINDOWS\\system32\\setupapi.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\System32\\winrnr.dll",target-name="C:\\WINDOWS\\System32\\winrnr.dll",host-name="C:\\WINDOWS\\System32\\winrnr.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\msctf.dll",target-name="C:\\WINDOWS\\system32\\msctf.dll",host-name="C:\\WINDOWS\\system32\\msctf.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\rasadhlp.dll",target-name="C:\\WINDOWS\\system32\\rasadhlp.dll",host-name="C:\\WINDOWS\\system32\\rasadhlp.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\system32\\hnetcfg.dll",target-name="C:\\WINDOWS\\system32\\hnetcfg.dll",host-name="C:\\WINDOWS\\system32\\hnetcfg.dll",symbols-loaded="0",thread-group="i1" =library-loaded,id="C:\\WINDOWS\\System32\\wshtcpip.dll",target-name="C:\\WINDOWS\\System32\\wshtcpip.dll",host-name="C:\\WINDOWS\\System32\\wshtcpip.dll",symbols-loaded="0",thread-group="i1" =thread-created,id="2",group-id="i1"
~"[New Thread 4220.0x155c]\n"
*running,thread-id="all"
*stopped,reason="breakpoint-hit",disp="keep",bkptno="18",frame={addr="0x00401c34",func="main",args=[],file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="119"},thread-id="1",stopped-threads="all" (gdb)
<-stack-info-depth>
^done,depth="1"
(gdb)
<-stack-list-arguments 1 0 0>
^done,stack-args=[frame={level="0",args=[]}]
(gdb)
<-stack-list-frames 0 0>
^done,stack=[frame={level="0",addr="0x00401c34",func="main",file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="119"}] (gdb)
<-thread-info>
^done,threads=[{id="2",target-id="Thread
4220.0x155c",frame={level="0",addr="0x7c90e514",func="ntdll!LdrAccessResource",args=[],from="C:\\WINDOWS\\system32\\ntdll.dll"},state="stopped"},{id="1",target-id="Thread 4220.0xe88",frame={level="0",addr="0x00401c34",func="main",args=[],file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="119"},state="stopped"}],current-thread-id="1" (gdb)
<-stack-list-arguments 1 0 0>
^done,stack-args=[frame={level="0",args=[]}]
(gdb)
<-stack-list-locals 1>
^done,locals=[]
(gdb)
<-data-evaluate-expression $fp>
^done,value="0x16eff94"
(gdb)
<-exec-next>
^running
*running,thread-id="1"
(gdb)
*running,thread-id="all"
=library-unloaded,id="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",target-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",host-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\dblib.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",target-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",host-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\\msvcr80.dll",thread-group="i1" =library-unloaded,id="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",target-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",host-name="w:\\md\\dev\\freepascal\\lib\\gh\\bin\\libiconv2.dll",thread-group="i1" ~"Cannot remove breakpoints because program is no longer writable.\nFurther execution is probably impossible.\n" *stopped,reason="end-stepping-range",frame={addr="0x00401c4d",func="main",args=[],file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="121"},thread-id="1",stopped-threads="all" ~"warning: Error removing breakpoint -108\n"
(gdb)
<-stack-info-depth>
^done,depth="1"
(gdb)
<-stack-list-arguments 1 0 0>
^done,stack-args=[frame={level="0",args=[]}]
(gdb)
<-stack-list-frames 0 0>
^done,stack=[frame={level="0",addr="0x00401c4d",func="main",file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="121"}] (gdb)
<-thread-info>
^done,threads=[{id="2",target-id="Thread
4220.0x155c",frame={level="0",addr="0x7c90e514",func="ntdll!LdrAccessResource",args=[],from="C:\\WINDOWS\\system32\\ntdll.dll"},state="stopped"},{id="1",target-id="Thread 4220.0xe88",frame={level="0",addr="0x00401c4d",func="main",args=[],file="dbtest.pas",fullname="w:\\md\\dev\\freepascal\\lib\\gh\\examples\\db\\mssql\\dbtest.pas",line="121"},state="stopped"}],current-thread-id="1" (gdb)
<-stack-list-arguments 1 0 0>
^done,stack-args=[frame={level="0",args=[]}]
(gdb)
<-stack-list-locals 1>
^done,locals=[]
(gdb)
<-data-evaluate-expression $fp>
^done,value="0x16eff94"
(gdb)
<-exec-next>
^error,msg="Warning:\nCannot insert breakpoint -110.\nError accessing memory address 0x7816cd30: Input/output error.\n"
(gdb)
<-break-delete 18>
^done
(gdb)
<kill>
&"kill\n"
=thread-exited,id="2",group-id="i1"
=thread-exited,id="1",group-id="i1"
=thread-group-exited,id="i1"
^done
(gdb)
<info program>
&"info program\n"
~"The program being debugged is not being run.\n"
^done
(gdb)
<-break-delete 15>
^done
(gdb)
<-break-delete 16>
^done
(gdb)
<-break-delete 17>
^done
(gdb)
<-file-exec-and-symbols >
=library-unloaded,id="C:\\WINDOWS\\system32\\ntdll.dll",target-name="C:\\WINDOWS\\system32\\ntdll.dll",host-name="C:\\WINDOWS\\system32\\ntdll.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\kernel32.dll",target-name="C:\\WINDOWS\\system32\\kernel32.dll",host-name="C:\\WINDOWS\\system32\\kernel32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\oleaut32.dll",target-name="C:\\WINDOWS\\system32\\oleaut32.dll",host-name="C:\\WINDOWS\\system32\\oleaut32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\advapi32.dll",target-name="C:\\WINDOWS\\system32\\advapi32.dll",host-name="C:\\WINDOWS\\system32\\advapi32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\rpcrt4.dll",target-name="C:\\WINDOWS\\system32\\rpcrt4.dll",host-name="C:\\WINDOWS\\system32\\rpcrt4.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\secur32.dll",target-name="C:\\WINDOWS\\system32\\secur32.dll",host-name="C:\\WINDOWS\\system32\\secur32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\gdi32.dll",target-name="C:\\WINDOWS\\system32\\gdi32.dll",host-name="C:\\WINDOWS\\system32\\gdi32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\user32.dll",target-name="C:\\WINDOWS\\system32\\user32.dll",host-name="C:\\WINDOWS\\system32\\user32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\msvcrt.dll",target-name="C:\\WINDOWS\\system32\\msvcrt.dll",host-name="C:\\WINDOWS\\system32\\msvcrt.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\ole32.dll",target-name="C:\\WINDOWS\\system32\\ole32.dll",host-name="C:\\WINDOWS\\system32\\ole32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\imm32.dll",target-name="C:\\WINDOWS\\system32\\imm32.dll",host-name="C:\\WINDOWS\\system32\\imm32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\lpk.dll",target-name="C:\\WINDOWS\\system32\\lpk.dll",host-name="C:\\WINDOWS\\system32\\lpk.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\usp10.dll",target-name="C:\\WINDOWS\\system32\\usp10.dll",host-name="C:\\WINDOWS\\system32\\usp10.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\shell32.dll",target-name="C:\\WINDOWS\\system32\\shell32.dll",host-name="C:\\WINDOWS\\system32\\shell32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\shlwapi.dll",target-name="C:\\WINDOWS\\system32\\shlwapi.dll",host-name="C:\\WINDOWS\\system32\\shlwapi.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\ws2_32.dll",target-name="C:\\WINDOWS\\system32\\ws2_32.dll",host-name="C:\\WINDOWS\\system32\\ws2_32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\ws2help.dll",target-name="C:\\WINDOWS\\system32\\ws2help.dll",host-name="C:\\WINDOWS\\system32\\ws2help.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",target-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",host-name="C:\\WINDOWS\\WinSxS\\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202\\comctl32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\comctl32.dll",target-name="C:\\WINDOWS\\system32\\comctl32.dll",host-name="C:\\WINDOWS\\system32\\comctl32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\System32\\mswsock.dll",target-name="C:\\WINDOWS\\System32\\mswsock.dll",host-name="C:\\WINDOWS\\System32\\mswsock.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\dnsapi.dll",target-name="C:\\WINDOWS\\system32\\dnsapi.dll",host-name="C:\\WINDOWS\\system32\\dnsapi.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\iphlpapi.dll",target-name="C:\\WINDOWS\\system32\\iphlpapi.dll",host-name="C:\\WINDOWS\\system32\\iphlpapi.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\mprapi.dll",target-name="C:\\WINDOWS\\system32\\mprapi.dll",host-name="C:\\WINDOWS\\system32\\mprapi.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\activeds.dll",target-name="C:\\WINDOWS\\system32\\activeds.dll",host-name="C:\\WINDOWS\\system32\\activeds.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\adsldpc.dll",target-name="C:\\WINDOWS\\system32\\adsldpc.dll",host-name="C:\\WINDOWS\\system32\\adsldpc.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\netapi32.dll",target-name="C:\\WINDOWS\\system32\\netapi32.dll",host-name="C:\\WINDOWS\\system32\\netapi32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\wldap32.dll",target-name="C:\\WINDOWS\\system32\\wldap32.dll",host-name="C:\\WINDOWS\\system32\\wldap32.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\atl.dll",target-name="C:\\WINDOWS\\system32\\atl.dll",host-name="C:\\WINDOWS\\system32\\atl.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\rtutils.dll",target-name="C:\\WINDOWS\\system32\\rtutils.dll",host-name="C:\\WINDOWS\\system32\\rtutils.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\samlib.dll",target-name="C:\\WINDOWS\\system32\\samlib.dll",host-name="C:\\WINDOWS\\system32\\samlib.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\setupapi.dll",target-name="C:\\WINDOWS\\system32\\setupapi.dll",host-name="C:\\WINDOWS\\system32\\setupapi.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\System32\\winrnr.dll",target-name="C:\\WINDOWS\\System32\\winrnr.dll",host-name="C:\\WINDOWS\\System32\\winrnr.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\msctf.dll",target-name="C:\\WINDOWS\\system32\\msctf.dll",host-name="C:\\WINDOWS\\system32\\msctf.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\rasadhlp.dll",target-name="C:\\WINDOWS\\system32\\rasadhlp.dll",host-name="C:\\WINDOWS\\system32\\rasadhlp.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\system32\\hnetcfg.dll",target-name="C:\\WINDOWS\\system32\\hnetcfg.dll",host-name="C:\\WINDOWS\\system32\\hnetcfg.dll",thread-group="i1" =library-unloaded,id="C:\\WINDOWS\\System32\\wshtcpip.dll",target-name="C:\\WINDOWS\\System32\\wshtcpip.dll",host-name="C:\\WINDOWS\\System32\\wshtcpip.dll",thread-group="i1" ^done
(gdb)
====================================================

Marcos Douglas

Ok, I looked through it. Nott much of a result. Except there is no way to fix it, other to get the GDB developers to fix it in GDB.

Though you might want to try gdb 7.0.50 from mingw. It seems that 7.3 and 7.4 have some sort of regression in thread handling (on a different and rather rare issue) (Not sure where 7.1 stands). Or go for 7.4 (I can send it to you with the required libs)

So what happens seems:

* The first F8
- seems to execute (next stop is 2 lines below)
- but throws a warning:
~"warning: Error removing breakpoint -108\n"

In this step several libraries are unloaded. It appears that for an unknown reason (and something beyond my knowledge) GDB did set a temporary break in one of that dll

At that time there is also a 2nd thread involved (Lots of dll on window start threads).

{id="2",target-id="Thread 4220.0x155c",

frame={level="0",addr="0x7c90e514",func="ntdll!LdrAccessResource",args=[],from="C:\\WINDOWS\\system32\\ntdll.dll"},state="stopped"}, {id="1",target-id="Thread 4220.0xe88",

frame={level="0",addr="0x00401c34",func="main",args=[],file="dbtest.pas",fullname="w:\\.....\\dbtest.pas",line="119"},state="stopped"}]

I do not know where that temp breakpoint was meant to go, or which thread.

* Then the next F8 fails

<-exec-next>
^error,msg="Warning:\nCannot insert breakpoint -110.\nError accessing memory address 0x7816cd30: Input/output error.\n"
(gdb)

That address must be in some library. Most likely in one of those that were unloaded

Your main thread is in your code, not in a library.

------------------------------

- I do not know why GDB expects a possible end of the single step in a library
- I do not know why gdb (at least if I guess correct) tries to set a break in an unloaded lib.

Can you send? I'll appreciate that, thanks.

Too my env:
Lazarus 0.9.31 r36175 FPC 2.6.1 i386-win32-win32/win64 FPC: http://svn.freepascal.org/svn/fpc/branches/fixes_2_6 GDB: http://svn.freepascal.org/svn/lazarus/binaries

Which GDB SVN do you think is the best choice?

Well, I understood what you said, but I can't read the debug info like you... I didn't understand anything. =|

Unfortunately, this is a work to GDB developers. =)

Thanks for all! I learned a lot.

Marcos Douglas

Marcos Douglas wrote

Which GDB SVN do you think is the best choice?

Not really sure. I have versions from 6.3 to 7.4. (for win 32). There is a testcase in the debugger/test/GDBMI directory

Most of the differences are handled by the IDE (like different text of error message)

Differences I do know:

- All versions over 7.0 have a problem with typecasting objects (stabs only) http://bugs.freepascal.org/view.php?id=19920
This is partly fixed by the IDE

- All 6.x and 7.3 / 7.4 versions (not sure about 7.1 / 7.2) have an issue with handling threads, in a rare race condition 7.0.50 does not have that issue

The issue occurs if a pause request (either hit "pause button" er modify/set/unset a breakpoint (which requires the ap to be paused and then continued)) is made, while the app is already paused. On Windows an app is paused via some windows function, opening a special thread in the app. (Not sure if the issue is triggered just by any thread, or by something else).

Normally the IDE will not send such a request to a paused app. But if the app has just hit a breakpoint, and the IDE had not yet read that notification from GDB, then it can happen....

- IIRC: Somewhere in 7.1 or 7.2 some essential suppor for using breakpoints when debugging a dll with starter app was added

- 7.4
Has some issue with "-break-insert +0"
The IDE only uses that as fallback (unless you change config), and can deal with this. So it does not currently cause any issues.

7.4 has new features, but the IDE does not support then yet... Otherwise, I haven't yet worked out where/if 7.4 differs significantly

Oh my... =)
There are many differences, many options to choice. Using a simple vision, I think the IDE should be use the last GDB that works fine in the major cases. What GDB version represents that?

The URL that I wrote gets the 7.3 version. That is the recommended by Lazarus Team?

Marcos Douglas

I cced to lazarus.

We should move the discussion

At the moment, I think Lazarus ships 7.3.2

http://svn.freepascal.org/svn/lazarus/binaries

So far I have no plans to update to 7.4 until either:
- I find some existing problem solved in it
- I start supporting new features

However, my tests so far, have not shown any problems when using 7.4.