Configure now aborts with a diagnostic if it detects a duplicate extension.

Backport of 864293481e6a8b8 + 01db32e2e6d17e

diff --git a/U/perl/Extensions.U b/U/perl/Extensions.U
index 0ae09be..d43c0d8 100644 (file)
--- a/U/perl/Extensions.U
+++ b/U/perl/Extensions.U
@@ -97,6 +97,25 @@ find_extensions='
                    fi;
                fi;
            else
+               echo " $known_extensions $nonxs_extensions" > $$.tmp;
+               if $contains " $this_ext " $$.tmp; then
+                   echo >&4;
+                   echo "Duplicate directories detected for extension $xxx" >&4;
+                   echo "Configure cannot correctly recover from this - shall I abort?" >&4;
+                   case "$knowitall" in
+                   "") dflt=y;;
+                   *) dflt=n;;
+                   esac;
+                   . ../UU/myread;
+                   case "$ans" in
+                   n*|N*) ;;
+                   *) echo >&4;
+                      echo "Ok.  Stopping Configure." >&4;
+                      echo "Please remove the duplicate directory (eg using git clean) and then re-run Configure" >&4;
+                       exit 1;;
+                   esac;
+                   echo "Ok.  You will need to correct config.sh before running make." >&4;
+               fi;
                $ls -1 $xxx > $$.tmp;
                if   $contains "\.xs$" $$.tmp > /dev/null 2>&1; then
                    known_extensions="$known_extensions $this_ext";