Re: bug-report: debug trap messes up pipestatus if containing command substitution

[Hengyang Zhao]

I missed a segment of my config when copy-pasting:

Bash Version: 5.0
Patch Level: 7
Release Status: release

On Mon, May 20, 2019 at 9:57 PM Hengyang Zhao <hzhao877502@gmail.com> wrote:

> +speng004@ucr.edu +yunduan.han@gmail.com
>
> On Mon, May 20, 2019 at 9:51 PM Hengyang Zhao <hzhao877502@gmail.com>
> wrote:
>
>> Dear bash developers,
>>
>> I found an unexpected behavior when engineering some code in a callback
>> of DEBUG trap. The code has been distilled to expose this behavior:
>>
>> ### BEGIN
>> my_func() {
>>   local x=$(:)
>> }
>> trap my_func DEBUG
>> false | true | false | true | false
>> echo ${PIPESTATUS[@]}
>> # expects 1 0 1 0 1
>> # gets 0 0 0 0 1
>> ### END
>>
>> Configuration Information:
>> Machine: x86_64
>> OS: linux-gnu
>> Compiler: gcc
>> Compilation CFLAGS: -O2 -g -pipe -Wall -Werror=format-security
>> -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions
>> -fstack-protector-strong -grecord-gcc-switches
>> -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1
>> -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic
>> -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection
>> -Wno-parentheses -Wno-format-security
>> uname output: Linux fedora 5.0.9-301.fc30.x86_64 #1 SMP Tue Apr 23
>> 23:57:35 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
>> Machine Type: x86_64-redhat-linux-gnu
>>
>> This also happens on many of my OSes running bash 4.x.
>>
>> I'm happy to provide further information if needed.
>>
>> Thank you,
>> Hengyang
>>
>