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Re: rmdir -p
>> [darcy%dilbert.druid.net@localhost:/usr/NetBSD/cvs/pkgsrc/graphics/librsvg] $
>> pkglint WARN: Makefile:38: The use of a leading "-" to suppress errors
>> is deprecated. 0 errors and 1 warnings found.
> It is better to express that explicitly via || true.
A leading - was added to make specifically to express the semantics of
"ignore errors from this command". || says "do this, and then, if it
fails, do that". That using it with an always-successful command as
the RHS has the effect of ignoring failures from the LHS is a side
effect of its primary purpose, via a comparatively little-known aspect
of its definition - that the exit status of the || construct is the
exit status of the last-executed command.
Thus, I would say that the "leading -" way is the explicit way to
suppress errors and the "|| true" way is a kludge based on a side
effect of a syntax designed for a different purpose.
Furthermore, leading - works regardless of shell, and does not force
make to shell the command if it doesn't contain metasyntax; || true
depends on the shell make uses using sh rules for ||, and does force
make to run a shell. (Not that either one is likely to matter much in
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