Re: perl/experimental FTBFS on m68k, sh4

Hi Niko!

On 7/8/19 6:01 PM, Niko Tyni wrote:
> The qemu-user specific thing is that $0 (= /proc/pid/cmdline) contains
> an absolute path to the binary there regardless of how it was actually
> invoked.
> 
> On normal systems:
> 
>   % sh -c 'echo $0'
>   sh
> 
> On qemu-user:
> 
>   $ sh -c 'echo $0'
>   /usr/bin/sh
> 
> It looks like the cflags.SH gets called in a different way in a
> subdirectory build, from Configure:2013 or so. In a subdirectory build
> it gets run with 'sh < cflags.SH' while in a "normal" build it gets run
> as 'sh cflags.SH'. The former causes $0 to contain '/usr/bin/sh' under
> qemu-user, and this then gets treated as an absolute path argument. So
> the code changes to the same path (here /usr/bin) and tries to create
> files there.
> 
> Looking at https://patchwork.kernel.org/patch/9633901/ I suspect
> the $0 handling in qemu-user is not easily fixed. I suppose the the
> Perl build machinery should handle this case just like it handles
> other quirks in weird systems and environments.
> 
> I'll file a bug separately.
Fantastic. Thanks so much for narrowing this down. Much appreciated.

This particular issue drove me nuts and I couldn't figure out what
the problem is. Glad you found out what the problem was.

PS: Can you CC me for the bug report you are filing?

Adrian