configure.ac: Remove conveniene symlinks before (re)creating them

Author: Matthias Koeppe

configure.ac

@@ -507,13 +507,15 @@ AC_CONFIG_COMMANDS(links, [
     SYMLINK="${ac_top_build_prefix}prefix"
     AS_IF([test -L "$SYMLINK" -o ! -e "$SYMLINK"], [
         AC_MSG_NOTICE([creating convenience symlink $SYMLINK -> $SAGE_LOCAL])
+        rm -f "$SYMLINK"
         ln -sf "$SAGE_LOCAL" "$SYMLINK"
     ], [
         AC_MSG_NOTICE([cannot create convenience symlink $SYMLINK -> $SAGE_LOCAL because the file exists and is not a symlink; this is harmless])
     ])
     SYMLINK="${ac_top_build_prefix}venv"
     AS_IF([test -L "$SYMLINK" -o ! -e "$SYMLINK"], [
         AC_MSG_NOTICE([creating convenience symlink $SYMLINK -> $SAGE_VENV])
+        rm -f "$SYMLINK"
         ln -sf "$SAGE_VENV" "$SYMLINK"
     ], [
         AC_MSG_NOTICE([cannot create convenience symlink $SYMLINK -> $SAGE_VENV because the file exists and is not a symlink; this is harmless])