Re: Out of order unwind entry warning

[Helge Deller <deller@gmx.de>]

Hi Dave,

> On 10/28/2009 12:19 AM, John David Anglin wrote:
>> From my understanding of things, it shouldn't be necessary to remove the
>>unwind info for unused weak  symbols if they aren't garbage collected.

What do you mean with "garbage collected" ?  "dropped from the executable" ?
AFAICS, the weak function was completely dropped from the vmlinux file.

Some more info:
The unwind function in the parisc linux kernel walks the (sorted!) unwind list.
If one entry is wrong this can lead to incorrect unwinding.

In this case:

<arch_mod_section_prepend>: [0x1011fc4c-0x1011fc74]   - non-weak function
           Entry_GR=1 Save_SP Total_frame_size=8
<arch_mod_section_prepend>: [0x1011fc4c-0x10167cf4]  - weak function
           Entry_GR=1 Save_SP Total_frame_size=8
<module_arch_cleanup>: [0x1011fc78-0x1011fcb8]
           Entry_GR=2 Save_SP Save_RP Total_frame_size=8

I see a those options:
a) drop the second (weak) unwind info entry
b) for the weak function, use the same start- and end-addresses as the non-weak entry.

Option b) would probably need some adjustments to the existing parisc
specific unwind function.

Helge