Re: Pending patches for generic build script

[Charles Wilson <cygwin at cwilson dot fastmail dot fm>]

Igor Pechtchanski wrote:

> > false || true
> >
> > As a bonus, this construct documents that this particular line can
> > return a false value.
>
>
> I see.  Well, this does look reasonably readable...  Another problem with
> "set +e" that I vaguely recall reading about is that it may not always be
> propagated into functions...  If you're willing to test this and make sure
> it always works properly, and if nobody else protests, I'll consider
> patching the generic-build-script.

Yes, I've never liked the silly looking '&& \' syntax in the gbs.  If 
propagation of 'set +e' into functions is a problem, then just have each 
function re-do it...


mkdirs() {(
  set +e
  cd ${topdir}
  rm -fr ${objdir} ${instdir} ${srcinstdir} || true
  mkdir -p ${objdir}
  mkdir -p ${instdir}
  mkdir -p ${srcinstdir}
)}

Plus, if the shell is changed from #!/bin/sh to #!/bin/bash, then you 
don't need the subshell -- because 'pushd' is available.  (Yes, I know 
you could do, even in sh, "CWD=`pwd`; cd ${topdir} ; .... ; cd ${CWD}" 
but there's another reason...)

I've noticed lately that sometimes, when launching configure from an 
environment where SHELL is /bin/sh (==ash), I get weird, 
non-deterministic errors:

"error: invalid feature name: shared"

when "--enable-shared" IS a valid feature for the package; but the error 
doesn't show up ALL the time.  This issue is what's made me have to run 
(portions) of the libtool test suite over and over before releasing it, 
because many of the tests which fail will EVENTUALLY succeed.  Or, I 
just configure with bash as my shell...the problem never seems to appear 
when using bash.

So, you could do:

#!/bin/bash
set +e
...
mkdirs() {
  set +e
  cd ${topdir}
  rm -fr ${objdir} ${instdir} ${srcinstdir} || true
  mkdir -p ${objdir}
  mkdir -p ${instdir}
  mkdir -p ${srcinstdir}
}

--
Chuck