Re: [PATCH] Cwrapper should not eat -- arguments

[Charles Wilson]

Ralf Wildenhues wrote:

> > Of course, if $build != $host, and $build does not have a suitable  
> > emulation environment, everything in the whole test suite will fail/skip  
> > anyway, so that concern may not be an issue...
>
> Again, I don't understand.  

1. in a cross-compile case
2. where you do not have an emulation environment for $host

no application that you link will be runnable.  So any test that depends 
on running a compiled executable will fail unless it is skipped. But it 
sure won't PASS.

> Just because we don't use the cwrapper in
> a test, doesn't mean that the test would now magically fail to pass "--"
> on to the real program. 

Okay, but now you have a wierd case. Suppose your test case relies on 
*running* the target executable, not just "I successfully linked it". 
There are several cases:

(1) native -- this should work everywhere. So you could have a target 
program that reports its args, and verify that it gets the passed-on 
'--' argument
   (a) on $host=cygwin|mingw, this will test the cwrapper
   (b) on all other $host, this will test the shell wrapper

(2) cross-to-mingw, $build has emulation environment -- this should 
work. Again, your target prog would act as above, and you could verify 
that '--' was passed on. [Aside: it could also report its env, so you 
could verify that the PATH was properly manipulated. But then the test 
would need to be different for different $host; in one case, it needs to 
verify LD_LIBRARY_PATH, on another, SHLIB_PATH, on another, PATH -- 
unless this particular testcase is going to be $host-specific]
   (a) ignoring the Aside, this will exercise/test the cwrapper in a 
cross environment

(3) cross-to-mingw, $build has no emulation environment. Will not work, 
because the cwrapper is a $host program (as is the target exe). You 
can't run it. You can't test it. All you can do is verify that it linked 
correctly.

(4) cross-to-cygwin, $build has emul env: currently won't work, because 
no support in cwrapper for this case. Coming soon.

(5) cross-to-cygwin, no emul env on $build: see (3).

(6) cross-to-[any but mingw|cygwin]: would exercise the shell wrapper, 
but the target executable will fail, because you can't run $host 
executables on $build.  So how do you verify that the shell wrapper is 
passing on the correct arguments? Replace the target executable with a 
$build executable, after the fact?

This is a LOT of special casing.

> It simply doesn't exercise the cwrapper, but
> hey, what's the problem with that?  It may just help to avoid a bug in
> the shell wrapper, too, given that it is exercised, and if neither, no
> problem either.

See above.

--
Chuck