From Fedora Project Wiki
No edit summary
No edit summary
Line 1: Line 1:
{{admon/important | Comments and Explanations | The page source contains comments providing guidance to fill out each section. They are invisible when viewing this page. To read it, choose the "view source" link.<br/> }}
{{admon/important | Comments and Explanations | The page source contains comments providing guidance to fill out each section. They are invisible when viewing this page. To read it, choose the "view source" link.<br/> }}


<!-- Self Contained or System Wide Change Proposal?
= Bash 5.0  
Use this guide to determine to which category your proposed change belongs to.
 
Self Contained Changes are:
* changes to isolated/leaf package without the impact on other packages/rest of the distribution
* limited scope changes without the impact on other packages/rest of the distribution
* coordinated effort within SIG with limited impact outside SIG functional area, accepted by the SIG
 
System Wide Changes are:
* changes that does not fit Self Contained Changes category touching
* changes that require coordination within the distribution (for example mass rebuilds, release engineering or other teams effort etc.)
* changing system defaults
 
For Self Contained Changes, sections marked as "REQUIRED FOR SYSTEM WIDE CHANGES" are OPTIONAL but FESCo/Wrangler can request more details (especially in case the change proposal category is
improper or updated to System Wide category). For System Wide Changes all fields on this form are required for FESCo acceptance (when applies). 
 
We request that you maintain the same order of sections so that all of the change proposal pages are uniform.
-->
 
<!-- The actual name of your proposed change page should look something like: Changes/Your_Change_Proposal_Name.  This keeps all change proposals in the same namespace -->
 
<!-- The actual name of your proposed change page should look something like: Changes/Your_Change_Proposal_Name.  This keeps all change proposals in the same namespace -->
= Bash 5.0 <!-- The name of your change proposal --> =


== Summary ==
== Summary ==
Line 31: Line 9:
nameref variables resolve and a number of potential out-of-bounds memory
nameref variables resolve and a number of potential out-of-bounds memory
errors discovered via fuzzing.
errors discovered via fuzzing.
<!-- A sentence or two summarizing what this change is and what it will do. This information is used for the overall changeset summary page for each release.
Note that motivation for the change should be in the Motivation section below, and this part should answer the question "What?" rather than "Why?". -->


== Owner ==
== Owner ==
<!--
For change proposals to qualify as self-contained, owners of all affected packages need to be included here. Alternatively, a SIG can be listed as an owner if it owns all affected packages.
This should link to your home wiki page so we know who you are.
-->
* Name: [[User:svashisht| Siteshwar Vashisht]]
* Name: [[User:svashisht| Siteshwar Vashisht]]
<!-- Include you email address that you can be reached should people want to contact you about helping with your change, status is requested, or technical issues need to be resolved. If the change proposal is owned by a SIG, please also add a primary contact person. -->
 
* Email: svashisht@redhat.com
* Email: svashisht@redhat.com
* Release notes owner: <!--- To be assigned by docs team [[User:FASAccountName| Release notes owner name]] <email address> -->
* Release notes owner:  
<!--- UNCOMMENT only for Changes with assigned Shepherd (by FESCo)
<!--- UNCOMMENT only for Changes with assigned Shepherd (by FESCo)
* FESCo shepherd: [[User:FASAccountName| Shehperd name]] <email address>
* FESCo shepherd: [[User:FASAccountName| Shehperd name]] <email address>

Revision as of 08:24, 24 January 2019

Important.png
Comments and Explanations
The page source contains comments providing guidance to fill out each section. They are invisible when viewing this page. To read it, choose the "view source" link.

= Bash 5.0

Summary

Upgrade bash to 5.0 release. This release fixes several outstanding bugs in bash-4.4 and introduces several new features. The most significant bug fixes are an overhaul of how nameref variables resolve and a number of potential out-of-bounds memory errors discovered via fuzzing.

Owner

  • Email: svashisht@redhat.com
  • Release notes owner:

Current status

  • Targeted release: Fedora 30
  • Last updated: 2019-01-24
  • Tracker bug: <will be assigned by the Wrangler>

Detailed Description

There are a number of changes to the expansion of $@ and $* in various contexts where word splitting is not performed to conform to a Posix standard interpretation, and additional changes to resolve corner cases for Posix conformance.

The most notable new features are several new shell variables: BASH_ARGV0, EPOCHSECONDS, and EPOCHREALTIME. The history builtin can remove ranges of history entries and understands negative arguments as offsets from the end of the history list. There is an option to allow local variables to inherit the value of a variable with the same name at a preceding scope. There is a new shell option that, when enabled, causes the shell to attempt to expand associative array subscripts only once (this is an issue when they are used in arithmetic expressions). The `globasciiranges' shell option is now enabled by default; it can be set to off by default at configuration time.

There are a few incompatible changes between bash-4.4 and bash-5.0. The changes to how nameref variables are resolved means that some uses of namerefs will behave differently, though upstream has tried to minimize the compatibility issues.


Benefit to Fedora

Bash is the default shell in Fedora and it will benefit from new features and performance improvements of the latest release.


Scope

  • Proposal owners: Upgrade bash to 5.0
  • Other developers: N/A (not a System Wide Change)
  • Policies and guidelines: N/A (not a System Wide Change)
  • Trademark approval: N/A (not needed for this Change)

Upgrade/compatibility impact

It should be minimum as this release is largely backward compatible.


How To Test

N/A (not a System Wide Change)

User Experience

Dependencies

N/A (not a System Wide Change)

Contingency Plan

  • Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
  • Contingency deadline: N/A (not a System Wide Change)
  • Blocks release? N/A (not a System Wide Change), Yes/No
  • Blocks product? product

Documentation

N/A (not a System Wide Change)

Release Notes

https://lists.gnu.org/archive/html/bug-bash/2019-01/msg00063.html