only test for -mno-cygwin if the target is mingw32
AC_PROG_CPP
dnl ** does the C compiler support the following options?
-FPTOOLS_CC_FLAG(-mno-cygwin,CC_SUPPORTS_MNO_CYGWIN)
-
-EXTRA_CC_OPTS="$CC_SUPPORTS_MNO_CYGWIN"
-SRC_CC_OPTS="-O $EXTRA_CC_OPTS"
-CPPFLAGS="$EXTRA_CC_OPTS $CPPFLAGS"
-AC_SUBST(SRC_CC_OPTS)
+case $TargetOS_CPP in
+mingw32)
+ FPTOOLS_CC_FLAG(-mno-cygwin,CC_SUPPORTS_MNO_CYGWIN)
+
+ EXTRA_CC_OPTS="$CC_SUPPORTS_MNO_CYGWIN"
+ SRC_CC_OPTS="-O $EXTRA_CC_OPTS"
+ CPPFLAGS="$EXTRA_CC_OPTS $CPPFLAGS"
+ AC_SUBST(SRC_CC_OPTS)
+ ;;
+*) ;;
+esac
dnl ** figure out how to do context diffs
FPTOOLS_PROG_DIFF