Re: [PATCH 2/2] kbuild: rename built-in.o to built-in.a

[Nicholas Piggin <npiggin@gmail.com>]

On Sun, 11 Feb 2018 13:38:04 +0900
Masahiro Yamada <yamada.masahiro@socionext.com> wrote:

> 2018-02-10 23:25 GMT+09:00 Nicholas Piggin <npiggin@gmail.com>:
> > Incremental linking is gone, so rename built-in.o to built-in.a, which
> > is the usual extension for archive files.
> >
> > This patch does two things, first is a simple search/replace:
> >
> > git grep -l 'built-in\.o' | xargs sed -i 's/built-in\.o/built-in\.a/g'
> >
> > The second is to invert nesting of nested text manipulations to avoid
> > filtering built-in.a out from libs-y2:
> >
> > -libs-y2 := $(filter-out %.a, $(patsubst %/, %/built-in.a, $(libs-y)))
> > +libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))
> >
> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com>  
> 
> 
> I think this is the right thing to do, but I have no idea
> why 'less kernel/built-in.a' shows strange output.
> Do you have a clue?
> 
> 
> Without this patch,
> 'emacs kernel/built-in.o'
> 'cat kernel/built-in.o'
> 'less kernel/built-in.o'
> 
> showed me the same content.
> 
> $ less kernel/built-in.o | head -n 10
> !<thin>
> //                                              2964      `
> fork.o/
> exec_domain.o/
> panic.o/
> cpu.o/
> exit.o/
> softirq.o/
> resource.o/
> sysctl.o/
> 
> 
> 
> 
> After applying this patch,
> 'less kernel/built-in.a' is strange.
> 
> 
> $ less kernel/built-in.a | head -n 10
> rw-r--r-- 0/0  60216 Jan  1 09:00 1970 kernel/fork.o
> rw-r--r-- 0/0   3648 Jan  1 09:00 1970 kernel/exec_domain.o
> rw-r--r-- 0/0  20552 Jan  1 09:00 1970 kernel/panic.o
> rw-r--r-- 0/0  87752 Jan  1 09:00 1970 kernel/cpu.o
> rw-r--r-- 0/0  34136 Jan  1 09:00 1970 kernel/exit.o
> rw-r--r-- 0/0  41448 Jan  1 09:00 1970 kernel/softirq.o
> rw-r--r-- 0/0  40904 Jan  1 09:00 1970 kernel/resource.o
> rw-r--r-- 0/0  60968 Jan  1 09:00 1970 kernel/sysctl.o
> rw-r--r-- 0/0   4472 Jan  1 09:00 1970 kernel/sysctl_binary.o
> rw-r--r-- 0/0  12472 Jan  1 09:00 1970 kernel/capability.o
> 
> 
> However, 'cat kernel/built-in.a' works as I expect.
> 
> $ cat  kernel/built-in.a | head -n 10
> !<thin>
> //                                              2964      `
> fork.o/
> exec_domain.o/
> panic.o/
> cpu.o/
> exit.o/
> softirq.o/
> resource.o/
> sysctl.o/
> 
> 
> 
> Is my 'less' insane?
> Or, is this intentional behavior of 'less'?

Interesting, my less does not do that. Instead of the raw contents
of the file, yours is providing output of `ar tv`, which is
reconstructing more of the archive metadata. I guess it is keyed
on the filename extension.

Do you have an alias for it, or maybe the distro patches the tool?
It seems a bit rude for your less tool to reformat data for you.

Thanks,
Nick