Re: large line number debugging support

[Daniel Berlin <dan@cgsoftware.com>]

On Wed, 19 Dec 2001, Paolo Molaro wrote:

> On 12/15/01 Daniel Berlin wrote:
> > > How does dwarf2 go with this?  ``gas -gdwarf2'' will select dwarf2
> > > assembler debug info.
> >
> > DWARF2 can do line numbers as large as you like, the opcodes take leb128
> > or sleb128, as opposed to some fixed size encoding.
>
> Uhm, still no luck:
>
> $ cat test-stabs.s
> .stabs "corlib.il",100,0,0,0
> .stabs "Void:t(0,1)=(0,1)",128,0,0,0
> .stabs "myfunc:F(0,1)",36,0,70000,0x0
> .stabs "",36,0,0,204
>
> $ as -gdwarf2 test-stabs.s -o test-stabs.o
> $ objdump -G test-stabs.o
>
> test-stabs.o:     file format elf32-i386
>
> Contents of .stab section:
>
> Symnum n_type n_othr n_desc n_value  n_strx String
>
> -1     HdrSym 0      4      00000038 1
> 0      SO     0      0      00000000 14     corlib.il
> 1      LSYM   0      0      00000000 24     Void:t(0,1)=(0,1)
> 2      FUN    0      4464   00000000 42     myfunc:F(0,1)
> 3      FUN    0      0      000000cc 0
>
> $ echo $((70000-4464))
> 65536
>
> It's still trucated at 65536. So, even if the information is saved in
> the file (from an hexdump it doesn't look so), it's not used correctly
> by objdump and gdb.
> My binutils version is:
> binutils           2.11.92.0.12.3-3
>
> Maybe I'm just doing something silly?

as -gdwarf-2 would generate line number debug info for the *assembler
source*, not translate your stabs commands into dwarf2 ones.
You need to output dwarf2 info instead of stabs.