[PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Samuel Tardieu]

This file is the only one involved in the compilation process which
still uses the /bin/bash path.

Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
---
 target/hexagon/idef-parser/prepare | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/hexagon/idef-parser/prepare b/target/hexagon/idef-parser/prepare
index 72d6fcbd21..cb3622d4f8 100755
--- a/target/hexagon/idef-parser/prepare
+++ b/target/hexagon/idef-parser/prepare
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #
 #  Copyright(c) 2019-2021 rev.ng Labs Srl. All Rights Reserved.
-- 
2.42.0

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Philippe Mathieu-Daudé]

On 23/11/23 22:15, Samuel Tardieu wrote:
> This file is the only one involved in the compilation process which
> still uses the /bin/bash path.
> 
> Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
> ---
>   target/hexagon/idef-parser/prepare | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Anton Johansson via]

On 23/11/23, Samuel Tardieu wrote:
> This file is the only one involved in the compilation process which
> still uses the /bin/bash path.
> 
> Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
> ---
>  target/hexagon/idef-parser/prepare | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/hexagon/idef-parser/prepare b/target/hexagon/idef-parser/prepare
> index 72d6fcbd21..cb3622d4f8 100755
> --- a/target/hexagon/idef-parser/prepare
> +++ b/target/hexagon/idef-parser/prepare
> @@ -1,4 +1,4 @@
> -#!/bin/bash
> +#!/usr/bin/env bash
>  
>  #
>  #  Copyright(c) 2019-2021 rev.ng Labs Srl. All Rights Reserved.
> -- 
> 2.42.0
> 
Reviewed-by: Anton Johansson <anjo@rev.ng>

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Philippe Mathieu-Daudé]

On 23/11/23 22:15, Samuel Tardieu wrote:
> This file is the only one involved in the compilation process which
> still uses the /bin/bash path.
> 
> Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
> ---
>   target/hexagon/idef-parser/prepare | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

Patch queued, thanks!

Phil.

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Michael Tokarev]

23.11.2023 23:57, Samuel Tardieu :
> This file is the only one involved in the compilation process which
> still uses the /bin/bash path.
> 
> Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
> ---
>   target/hexagon/idef-parser/prepare | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/hexagon/idef-parser/prepare b/target/hexagon/idef-parser/prepare
> index 72d6fcbd21..cb3622d4f8 100755
> --- a/target/hexagon/idef-parser/prepare
> +++ b/target/hexagon/idef-parser/prepare
> @@ -1,4 +1,4 @@
> -#!/bin/bash
> +#!/usr/bin/env bash

What's the reason for this indirection?  bash has been /bin/bash for decades,
it is used this way in many other places in qemu code and in other projects.
Yes I know about current move /bin => /usr/bin etc, but the thing is that
traditional paths like this one (or like /bin/sh) is not going away any time
soon.  What's the matter here?

/mjt

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Samuel Tardieu]

Michael Tokarev <mjt@tls.msk.ru> writes:

>> -#!/bin/bash
>> +#!/usr/bin/env bash
>
> What's the reason for this indirection?  bash has been /bin/bash 
> for decades,
> it is used this way in many other places in qemu code and in 
> other projects.
> Yes I know about current move /bin => /usr/bin etc, but the 
> thing is that
> traditional paths like this one (or like /bin/sh) is not going 
> away any time
> soon.  What's the matter here?

In addition to Stefan's answer, some modern systems use a per-user 
file system hierarchy where each user (or even each environment 
development for a user)  gets a global set of directories with 
only the applications they want. This is done either through 
adding each application directory into the user PATH or by using a 
set of user-specific bin/lib/... directories full of symlinks to 
the chosen applications.

In those environments, /usr/bin might only contain "env", such as 
"/usr/bin/env application" works. This is the case for example on 
NixOS, which is more and more used in research environments for 
their easily reproducible build environments.

  Sam
-- 
Samuel Tardieu
Télécom Paris - Institut Polytechnique de Paris

Re: [PATCH] target/hexagon/idef-parser/prepare: use env to invoke bash

[Stefan Weil via]

Am 25.12.23 um 09:05 schrieb Michael Tokarev:
> 23.11.2023 23:57, Samuel Tardieu :
>> This file is the only one involved in the compilation process which
>> still uses the /bin/bash path.
>>
>> Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
>> ---
>>   target/hexagon/idef-parser/prepare | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/target/hexagon/idef-parser/prepare 
>> b/target/hexagon/idef-parser/prepare
>> index 72d6fcbd21..cb3622d4f8 100755
>> --- a/target/hexagon/idef-parser/prepare
>> +++ b/target/hexagon/idef-parser/prepare
>> @@ -1,4 +1,4 @@
>> -#!/bin/bash
>> +#!/usr/bin/env bash
> 
> What's the reason for this indirection?  bash has been /bin/bash for 
> decades,
> it is used this way in many other places in qemu code and in other 
> projects.
> Yes I know about current move /bin => /usr/bin etc, but the thing is that
> traditional paths like this one (or like /bin/sh) is not going away any 
> time
> soon.  What's the matter here?
> 
> /mjt
> 

On MacOS /bin/bash is the pre-installed bash:

% /bin/bash --version
GNU bash, version 3.2.57(1)-release (arm64-apple-darwin23)
Copyright (C) 2007 Free Software Foundation, Inc.

With /usr/bin/env I get a recent one from Homebrew:

% /usr/bin/env bash --version
GNU bash, version 5.2.21(1)-release (aarch64-apple-darwin23.0.0)
Copyright (C) 2022 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
<http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

So if a bash script uses bash syntax which was added after 2007, that 
would not work with /bin/bash. That's why I had to use the indirection 
for another open source project. I don't know whether the QEMU bash 
scripts require a newer version of bash.

Regards
Stefan