Call for volunteer: dwarf2 testing

[Eric Pouech]

As you may have seen, there's now some support for the dwarf2 debug 
format (instead of stabs) in the Wine tree
I'd like to get some feedback on the overall feedback on how it behaves.
To do so, you need to reconfigure Wine with something like
CFLAGS="$CFLAGS -gdwarf-2" ./configure
and then make clean; make (so that all modules are recompiled with 
proper format)

Normal debugging should be available with winedbg.
If something goes wrong, please indicate:
- console messages
- error items
- steps that led to it
- version of gcc used

TIA

[Paul Romanyszyn]

Eric Pouech wrote:
> As you may have seen, there's now some support for the dwarf2 debug 
> format (instead of stabs) in the Wine tree
> I'd like to get some feedback on the overall feedback on how it behaves.
> To do so, you need to reconfigure Wine with something like
> CFLAGS="$CFLAGS -gdwarf-2" ./configure
> and then make clean; make (so that all modules are recompiled with 
> proper format)
>
> Normal debugging should be available with winedbg.
> If something goes wrong, please indicate:
> - console messages
> - error items
> - steps that led to it
> - version of gcc used
>
> TIA

running a 16 bit application from bug Bug 5493
now gives an a continuous list of 
fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
instead of continuous page faulting between on the lookup.
What traces do you need and I will add them to that bug.

That bugs url links to the zip of the exe's with instructions on how to 
reproduce.

gcc (GCC) 4.0.1 (4.0.1-5mdk for Mandriva Linux release 2006.0)

Paul R.

[Eric Pouech]

running a 16 bit application from bug Bug 5493
> now gives an a continuous list of 
> fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
> instead of continuous page faulting between on the lookup.
> What traces do you need and I will add them to that bug.

does the attached patch help ?
A+
> From nobody Mon Sep 17 00:00:00 2001

From: Eric Pouech 
Date: Sat, 1 Jul 2006 11:38:10 +0200
Subject: [PATCH] [DbgHelp]: dwarf & variable with const values

- properly handle variable with const value (ie without
  location) in dwarf code

---

dlls/dbghelp/dwarf.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

5d683a5bfdb679fe617ced7b9070756c29d45a85
diff --git a/dlls/dbghelp/dwarf.c b/dlls/dbghelp/dwarf.c
index 01250a5..a618986 100644
--- a/dlls/dbghelp/dwarf.c
+++ b/dlls/dbghelp/dwarf.c
@@ -1050,20 +1050,20 @@ static void dwarf2_parse_variable(dwarf2
                                   dwarf2_debug_info_t* di)
 {
     struct symt* param_type;
-    union attribute loc;
+    union attribute name, loc, value;
     BOOL is_pmt = di->abbrev->tag == DW_TAG_formal_parameter;

TRACE("%s, for %s\n", dwarf2_debug_ctx(subpgm->ctx), dwarf2_debug_di(di));

param_type = dwarf2_lookup_type(subpgm->ctx, di);
-    if (dwarf2_find_attribute(di, DW_AT_location, &loc))
+    dwarf2_find_name(subpgm->ctx, di, &name, "parameter");
+    if (dwarf2_find_attribute(di, DW_AT_location, &loc) && loc.block)
     {
         union attribute name;
         union attribute ext;
         long offset;
         int in_reg;

-        dwarf2_find_name(subpgm->ctx, di, &name, "parameter");
         offset = dwarf2_compute_location(subpgm->ctx, loc.block, &in_reg);
    TRACE("found parameter %s/%ld (reg=%d) at %s\n",
               name.string, offset, in_reg, dwarf2_debug_ctx(subpgm->ctx));
@@ -1094,6 +1094,10 @@ static void dwarf2_parse_variable(dwarf2
             break;
         }
     }
+    if (dwarf2_find_attribute(di, DW_AT_const_value, &value))
+    {
+        FIXME("NIY (const value %08lx for %s\n", value.uvalue, name.string);
+    }
     if (is_pmt && subpgm->func && subpgm->func->type)
         symt_add_function_signature_parameter(subpgm->ctx->module,
                                               (struct symt_function_signature*)subpgm->func->type,

[Paul Romanyszyn]

Eric Pouech wrote:
> running a 16 bit application from bug Bug 5493
> > now gives an a continuous list of 
> > fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
> > instead of continuous page faulting between on the lookup.
> > What traces do you need and I will add them to that bug.
>
> does the attached patch help ?
> A+
> > From nobody Mon Sep 17 00:00:00 2001
>
> From: Eric Pouech 
> Date: Sat, 1 Jul 2006 11:38:10 +0200
> Subject: [PATCH] [DbgHelp]: dwarf & variable with const values
> - properly handle variable with const value (ie without
>
> location) in dwarf code
>
> dlls/dbghelp/dwarf.c |   10 +++++++---
> 1 files changed, 7 insertions(+), 3 deletions(-)
>
> 5d683a5bfdb679fe617ced7b9070756c29d45a85
> diff --git a/dlls/dbghelp/dwarf.c b/dlls/dbghelp/dwarf.c
> index 01250a5..a618986 100644
> --- a/dlls/dbghelp/dwarf.c
> +++ b/dlls/dbghelp/dwarf.c
> @@ -1050,20 +1050,20 @@ static void dwarf2_parse_variable(dwarf2
>                                   dwarf2_debug_info_t* di)
> {
>     struct symt* param_type;
> - union attribute loc;
> -
>
> union attribute name, loc, value;
> BOOL is_pmt = di->abbrev->tag == DW_TAG_formal_parameter;
>
> TRACE("%s, for %s\n", dwarf2_debug_ctx(subpgm->ctx), dwarf2_debug_di(di));
>
> param_type = dwarf2_lookup_type(subpgm->ctx, di);
> - if (dwarf2_find_attribute(di, DW_AT_location, &loc))
> - dwarf2_find_name(subpgm->ctx, di, &name, "parameter");
> - if (dwarf2_find_attribute(di, DW_AT_location, &loc) && loc.block)
> {
>    union attribute name;
>    union attribute ext;
>    long offset;
>    int in_reg;
> -
>    dwarf2_find_name(subpgm->ctx, di, &name, "parameter");
>   offset = dwarf2_compute_location(subpgm->ctx, loc.block, &in_reg);
> TRACE("found parameter %s/%ld (reg=%d) at %s\n",
>             name.string, offset, in_reg, dwarf2_debug_ctx(subpgm->ctx));
>
> @@ -1094,6 +1094,10 @@ static void dwarf2_parse_variable(dwarf2
>             break;
>         }
>     }
> - if (dwarf2_find_attribute(di, DW_AT_const_value, &value))
> - {
> -
>    FIXME("NIY (const value %08lx for %s\n", value.uvalue, name.string);
> - }
> if (is_pmt && subpgm->func && subpgm->func->type)
>    symt_add_function_signature_parameter(subpgm->ctx->module,
>                                          (struct symt_function_signature*)subpgm->func->type,

This app is downloadable and takes only a few steps to reproduce.

Recompiled with that patch using the CFLAGS="$CFLAGS -gdwarf-2" ./configure
and this it the console output

wine: Unhandled page fault on read access to 0x00001d88 at address 
0x18e7:0x000018d2 (thread 0010), starting debugger...
WineDbg starting on pid 0xa
Unhandled exception: page fault on read access to 0x00001d88 in 16-bit 
code (18e7:18d2).
fixme:dbghelp:addr_to_linear Failed to linearize address 101a:00009f0d 
(mode 0)
In 16 bit mode.
Register dump:
 CS:18e7 SS:1b37 DS:191f ES:1a6f FS:003b GS:0033
 IP:18d2 SP:540e BP:5416 FLAGS:0206(   - 00      - RIP1)
 AX:500e BX:5422 CX:0000 DX:0000 SI:0000 DI:1c10
Stack dump:
0x1b37:0x540e:  1c10 0000 18e7 1b37 5485 153b 1a9f 0000
0x1b37:0x541e:  0032 0000 5436 0944 18e7 1270 1ba7 0008
0x1b37:0x542e:  1d5c 0000 0032 1b37 5441 1481 1ab7 0008
0323: sel=191f base=7fe30818 limit=00002d9f 16-bit rw-
034d: sel=1a6f base=7deac750 limit=00001fff 16-bit rw-
fixme:ntdll:RtlNtStatusToDosErrorNoTeb no mapping for c0000119
Backtrace:
=>1 0x18e7:0x18d2 (0x18e7:0x18d2)
  2 0x1a9f:0x153b (0x1a9f:0x153b)
  3 0x101a:0x9f0d (0x101a:0x9f0d)
  4 0x1aef:0x1cdf (0x1aef:0x1cdf)
  5 0x1aef:0x1b9e (0x1aef:0x1b9e)
  6 0x1b17:0x1447 (0x1b17:0x1447)
fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
information for kernel32<elf>
fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
wine: Unhandled page fault on read access to 0x55ac7760 at address 
0x7faba0f8 (thread 0012), starting debugger...
WineDbg starting on pid 0x11
Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
code (0x7faba0f8).
fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
information for dbghelp<elf>
fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
wine: Unhandled page fault on read access to 0x55ac7760 at address 
0x7faba0f8 (thread 0014), starting debugger...
WineDbg starting on pid 0x13
Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
code (0x7faba0f8).
fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
information for dbghelp<elf>
fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
wine: Unhandled page fault on read access to 0x55ac7760 at address 
0x7faba0f8 (thread 0016), starting debugger...
WineDbg starting on pid 0x15
Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
code (0x7faba0f8).
fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
information for dbghelp<elf>
fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
wine: Unhandled page fault on read access to 0x55ac7760 at address 
0x7faba0f8 (thread 0018), starting debugger...
WineDbg starting on pid 0x17
Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
code (0x7faba0f8).
....
continues until ctrl C

[Eric Pouech]

Paul Romanyszyn wrote:
> This app is downloadable and takes only a few steps to reproduce.

Thanks for testing Paul... the app is not the culprit as the fault 
occurs while loading kernel32 debug information... you should get the 
same error for any app you load under winedbg (if you load kernel32 symbols)
that's why you get endless errors: crash in winedbg, which (as any app) 
relaunches winedbg for a debugging...

(and moreover, it seems there are 16bit related issues in winedbg, but 
that's a different story)
> fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75

ok, the first patch did fix the error, but now we run into another one
I'll fix it later
> wine: Unhandled page fault on read access to 0x55ac7760 at address 
> 0x7faba0f8 (thread 0012), starting debugger...
> WineDbg starting on pid 0x11
> Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
> code (0x7faba0f8).
> fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
> information for dbghelp<elf>
> fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
> wine: Unhandled page fault on read access to 0x55ac7760 at address 
> 0x7faba0f8 (thread 0014), starting debugger...
> WineDbg starting on pid 0x13
> Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
> code (0x7faba0f8).
> fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
> information for dbghelp<elf>
> fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
> wine: Unhandled page fault on read access to 0x55ac7760 at address 
> 0x7faba0f8 (thread 0016), starting debugger...
> WineDbg starting on pid 0x15
> Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
> code (0x7faba0f8).
> fixme:dbghelp:elf_load_debug_info_from_map Alpha-support for Dwarf2 
> information for dbghelp<elf>
> fixme:dbghelp_dwarf:dwarf2_compute_location Unhandled attr op: 75
> wine: Unhandled page fault on read access to 0x55ac7760 at address 
> 0x7faba0f8 (thread 0018), starting debugger...
> WineDbg starting on pid 0x17
> Unhandled exception: page fault on read access to 0x55ac7760 in 32-bit 
> code (0x7faba0f8).
> ....
> continues until ctrl C