The change in commit 898be3e0415c6d which made completely
unrecognized OSes cause an error_exit "Unsupported host OS"
has some unfortunate unintended effects:
* if you run 'configure --help' on an unsupported host OS
(eg if intending to use it as a build machine for a
cross compile to a supported host) then the message
is printed instead of --help
* if the C compiler doesn't work or is missing (eg if
you passed an incorrect --cross-prefix by mistake)
the message is printed instead of the more useful
'compiler does not exist or does not work' message
Fix this by postponing the error_exit in this situation
until later, when we have already identified the more
useful cases for this.
The long term fix for this would be to move handling
of --help much further up in the configure script,
and make its output not dependent on checks that configure
runs. However for 2.9 this would be too invasive.
Reported-by: Stefan Weil <s...@weilnetz.de>
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
configure | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/configure b/configure
index 82966f7..8820036 100755
--- a/configure
+++ b/configure
@@ -323,6 +323,7 @@ replication="yes"
supported_cpu="no"
supported_os="no"
+bogus_os="no"
# parse CC options first
for opt do
@@ -695,7 +696,10 @@ Linux)
supported_os="yes"
;;
*)
- error_exit "Unsupported host OS $targetos"
+ # This is a fatal error, but don't report it yet, because we
+ # might be going to just print the --help text, or it might
+ # be the result of a missing compiler.
+ bogus_os="yes"
;;
esac
@@ -1461,6 +1465,14 @@ if ! compile_prog ; then
error_exit "\"$cc\" cannot build an executable (is your linker broken?)"
fi
+if test "$bogus_os" = "yes"; then
+ # Now that we know that we're not printing the help and that
+ # the compiler works (so the results of the check_defines we used
+ # to identify the OS are reliable), if we didn't recognize the
+ # host OS we should stop now.
+ error_exit "Unsupported host OS $targetos"
+fi
+
# Check that the C++ compiler exists and works with the C compiler
if has $cxx; then
cat > $TMPC <<EOF
--
2.7.4
