gcc-3.0 and libstdc++: More interesting configure problems

[Daniel Jacobowitz <dmj+ at andrew dot cmu dot edu>]

(This is all inside the libstdc++ v3 directory; for reference, the
toplevel config.cache in the object directory seems to be correct and
have none of these issues!)

Using the version of configure shipped in the gcc 3.0 tarball (I didn't
regenerate it with a local autoconf, so that's not the problem...) I
first configured with /bin/sh = /bin/bash, and I got lines like this in
config.cache:

ac_cv_prog_CXXCPP=${ac_cv_prog_CXXCPP=$'\'mips_fp_le-g++ -E\''}

I only had CC, CXX, and CPP in the environment (which got the same
treatment).  Configure fabricated the above out of thin air.
Now, I'm not entirely sure where that's coming from, or what it's
supposed to mean.  It evaluates roughly right in bash:

bash$ echo $ac_cv_prog_CXXCPP
'mips_fp_le-g++ -E'

(is that really what's supposed to come out of it?)

But not in other shells.
% ash
$ ac_cv_prog_CXXCPP=${ac_cv_prog_CXXCPP=$'\'mips_fp_le-g++ -E\''}
> Syntax error: Unterminated quoted string

Is autoconf really generating this, or did my bash go insane?  It looks
as if it may actually be bash's fault; bash has this propensity for
sticking dollar signs on the beginning of quoted strings.  And just to
make everyone happier, I get config.cache entries like:

ac_cv_prog_CC=${ac_cv_prog_CC=''\''mips_fp_le-gcc'\'''}

if I change /bin/sh to be ash.  I don't know if those are right either,
but I don't think they are.


My shells aren't insane, really!

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer