Caught by -Werror

We use the in-place windres, which isn't guaranteed to work with the
stage0 compiler.

hppa1, m68k

We avoid calling "rm -rf" with no file arguments; this fixes cleaning
on Solaris, where that fails.

We also check for suspicious arguments: anything containing "..",
starting "/", or containing a "*" (you need to call $(wildcard ...)
yourself now if you really want globbing). This should make things
a little safer.

cygwin's /bin/install doesn't set file modes correctly if the
destination path is a C: style path:

$ /bin/install -c -m 644 foo /cygdrive/c/cygwin/home/ian/foo2
$ /bin/install -c -m 644 foo c:/cygwin/home/ian/foo3
$ ls -l foo*
-rw-r--r-- 1 ian None 0 2011-01-06 18:28 foo
-rw-r--r-- 1 ian None 0 2011-01-06 18:29 foo2
-rwxrwxrwx 1 ian None 0 2011-01-06 18:29 foo3

This causes problems for bindisttest/checkBinaries.sh which then
thinks that e.g. the userguide HTML files are binaries.

We therefore use a /cygdrive path if we are on cygwin

This was done as part of an honours thesis at UNSW, the paper describing the
work and results can be found at:

http://www.cse.unsw.edu.au/~pls/thesis/davidt-thesis.pdf

A Homepage for the backend can be found at:

http://hackage.haskell.org/trac/ghc/wiki/Commentary/Compiler/Backends/LLVM

Quick summary of performance is that for the 'nofib' benchmark suite, runtimes
are within 5% slower than the NCG and generally better than the C code
generator.  For some code though, such as the DPH projects benchmark, the LLVM
code generator outperforms the NCG and C code generator by about a 25%
reduction in run times.

We now regenerate them when installing, which means the path for perl
doesn't get baked in

Patches from Goetz Isenmann <info@goetz-isenmann.de>, slightly updated
for HEAD (the method for configuring platforms in configure.ac has
changed).

This means we can remove some conditional stuff from the Makefiles,
and means the testsuite doesn't have to work out whether or not it's
on Windows.

Add some comments and better error reporting

The ${1+"$@"} was being evaluated by make, rather than being escaped.

I've also added some missing $s to some makefiles. These aren't
technically necessary, but it's nice to be consistent.