configure: rust support requires Python

Add error message to warn the user.

diff --git a/configure.ac b/configure.ac
index 3063f6da3366b4d928ec574cb3405375245224ae..6515b3f26407cb8373ef8af9f16f3158e398b193 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -2231,6 +2231,14 @@ fi
     if test "x$enable_rust" != "xyes" && test "x$enable_rust" != "xyes (default)"; then
       enable_rust="no"
     elif test "x$enable_python" != "xyes" && test ! -f rust/gen/c-headers/rust-core-gen.h; then
+      if test "x$enable_rust" = "xyes"; then
+        echo ""
+        echo "   ERROR! Rust support requires Python."
+        echo
+        echo "   Ubuntu: apt install python"
+        echo ""
+        exit 1
+      fi
       enable_rust="no"
     else
       # Rust require jansson (json support).