Bug 840126

Summary: redundant DW_TAG_GNU_call_site_parameter-DW_AT_abstract_origin
Product: [Fedora] Fedora Reporter: Jan Kratochvil <jan.kratochvil>
Component: dwzAssignee: Jakub Jelinek <jakub>
Status: CLOSED EOL QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: low Docs Contact:
Priority: unspecified    
Version: 19CC: jakub, jan.kratochvil
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
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Clone Of: Environment:
Last Closed: 2015-02-17 14:21:02 UTC Type: Bug
Regression: --- Mount Type: ---
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Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Flags
xorg-x11-server-1.12.3-1.fc18 Xorg.debug.xz original
none
xorg-x11-server-1.12.3-1.fc18 Xorg.debug.xz dwz-optimized none

Description Jan Kratochvil 2012-07-13 19:23:34 UTC
Description of problem:
Currently dwz-optimized DWARF may cause GDB internal-error (Bug 839596).
Going to fix GDB but that DWARF construct has no use anyway so posting it as missed DWZ optimization here.

Version-Release number of selected component (if applicable):
dwz-0.5-1.fc18.x86_64

How reproducible:
Always.

Steps to Reproduce:
dwz Xorg.debug

original Xorg.debug:
 <0><1409ed>: Abbrev Number: 1 (DW_TAG_compile_unit)
 <2><14637c>: Abbrev Number: 50 (DW_TAG_formal_parameter)
    <14637d>   DW_AT_name        : key
    <146381>   DW_AT_decl_file   : 2
    <146382>   DW_AT_decl_line   : 114
    <146383>   DW_AT_type        : <0x14639b>
 <2><146711>: Abbrev Number: 66 (DW_TAG_GNU_call_site)
    <146712>   DW_AT_low_pc      : 0x48894d
    <14671a>   DW_AT_abstract_origin: <0x146595>
 <3><14671e>: Abbrev Number: 74 (DW_TAG_GNU_call_site_parameter)
    <14671f>   DW_AT_abstract_origin: <0x14637c>
    <146723>   DW_AT_GNU_call_site_value: 3 byte block: f3 1 54         (DW_OP_GNU_entry_value: (DW_OP_reg4 (rsi)))
not found: DW_OP_GNU_parameter_ref: <0x14637c>

optimized Xorg.debug:
 <0><1c2a8>: Abbrev Number: 2 (DW_TAG_partial_unit)
 <2><1c2dc>: Abbrev Number: 96 (DW_TAG_formal_parameter)
    <1c2dd>   DW_AT_name        : key
    <1c2e1>   DW_AT_decl_file   : 2
    <1c2e2>   DW_AT_decl_line   : 114
    <1c2e3>   DW_AT_type        : <0x1c2f5>
 <0><110990>: Abbrev Number: 79 (DW_TAG_compile_unit)
 <2><1134cd>: Abbrev Number: 115 (DW_TAG_GNU_call_site)
    <1134ce>   DW_AT_low_pc      : 0x48894d
    <1134d6>   DW_AT_abstract_origin: <0x113370>
 <3><1134d8>: Abbrev Number: 106 (DW_TAG_GNU_call_site_parameter)
    <1134d9>   DW_AT_abstract_origin: <0x1c2dc>
    <1134dd>   DW_AT_GNU_call_site_value: 3 byte block: f3 1 54         (DW_OP_GNU_entry_value: (DW_OP_reg4 (rsi)))
not found: DW_OP_GNU_parameter_ref: <0x1c2dc>

In optimized DWARF DW_TAG_GNU_call_site_parameter-DW_AT_abstract_origin points outside of its CU which was problem for GDB.

But as no callee is referencing this DIE <0x1c2dc> by DW_OP_GNU_parameter_ref this DIE can be dropped.  No other CU can use the intra-cu binding DW_OP_GNU_parameter_ref-DW_TAG_GNU_call_site_parameter-DW_AT_abstract_origin.

Comment 1 Jan Kratochvil 2012-07-13 19:28:32 UTC
Created attachment 598155 [details]
xorg-x11-server-1.12.3-1.fc18 Xorg.debug.xz original

Comment 2 Jan Kratochvil 2012-07-13 19:30:43 UTC
Created attachment 598157 [details]
xorg-x11-server-1.12.3-1.fc18 Xorg.debug.xz dwz-optimized

Comment 3 Jan Kratochvil 2012-07-13 19:46:30 UTC
As DW_OP_GNU_parameter_ref uses CU-relative reference in fact DW_TAG_GNU_call_site_parameter-DW_AT_abstract_origin cannot be moved into DW_TAG_partial_unit even if it was referenced (dwz probably already solves it although I do not know).

Comment 4 Fedora End Of Life 2013-04-03 15:05:43 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 19 development cycle.
Changing version to '19'.

(As we did not run this process for some time, it could affect also pre-Fedora 19 development
cycle bugs. We are very sorry. It will help us with cleanup during Fedora 19 End Of Life. Thank you.)

More information and reason for this action is here:
https://fedoraproject.org/wiki/BugZappers/HouseKeeping/Fedora19

Comment 5 Fedora End Of Life 2015-01-09 17:15:18 UTC
This message is a notice that Fedora 19 is now at end of life. Fedora 
has stopped maintaining and issuing updates for Fedora 19. It is 
Fedora's policy to close all bug reports from releases that are no 
longer maintained. Approximately 4 (four) weeks from now this bug will
be closed as EOL if it remains open with a Fedora 'version' of '19'.

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Comment 6 Fedora End Of Life 2015-02-17 14:21:02 UTC
Fedora 19 changed to end-of-life (EOL) status on 2015-01-06. Fedora 19 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

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