Re: bsd sed / make vs bsd sed / make

From: Kyle Evans <kevans_at_FreeBSD.org>
Date: Thu, 25 Apr 2024 17:43:42 UTC
On 4/25/24 12:36, Tomek CEDRO wrote:
> Hello world :-)
> 
> Are there any SED and MAKE experts around? :-)
> 
> There is a piece of Makefile within NuttX RTOS simulator code that
> creates the linker scripts. I would like to fix the upstream so it
> builds out of the box on FreeBSD (*BSD).
> 
> sed -e '/====/,/====/!d;//d' -e 's/__executable_start/_stext/g' \
>       -e 's/^\(\s\+\)\(\.init_array\)/\1\2 : { }\n\1.sinit/g' \
>       -e 's/^\(\s\+\)\(\.fini_array\)/\1\2 : { }\n\1.einit/g' \
>       -e 's/__init_array_start/_sinit/g' -e 's/__init_array_end/_einit/g' \
>       -e 's/__fini_array_start/_sfini/g' -e
> 's/__fini_array_end/_efini/g' >nuttx.ld
 >

Everything about this is cursed.  IMO you should propose switching these 
to EREs (-E) and fixing all of the escaped things as appropriate for 
that switch, then substituting [[:space:]] in for \s to make them 
compliant expressions.


> 
> It does not work with BSD sed but when I replace this with gsed all works fine.
> 
> BSD sed complalins about trailinig backslash:
> 
> sed: 1: "s/^\(\s\+\)\(\.init_arr ...": RE error: trailing backslash (\)
> 
> Is there a way to fix that part so it works both with GNU sed and BSD
> sed? The easiest way would be adding ${SEDCMD} set to "gsed" on BSD
> and "sed" for the others (macOS also seems to use gnu sed).
> 

The ports infrastructure also has a BINARY_ALIAS that can be used to 
install gsed as sed for just this build, assuming nothing that uses 
these 'enhanced' expressions hardcodes a path to sed.

Thanks,

Kyle Evans