+dnl OK, so we're in the MSYS case. hardtop looks like /c/....
+dnl We want to make hardtop_plat into c:/...
+dnl Stop using [] for quotes temporarily, so we can use [] in the sed regexp
+changequote(, )dnl
+ hardtop_plat=`echo ${hardtop} | sed -e 's@^/\\([a-zA-Z]\\)/@\\1:/@g'`
+changequote([, ])dnl