Print version mismatches, DELETE AFTER DEBUGING

Author: mxamin

src/lxml.c

@@ -84,7 +84,19 @@ static int PyXmlSec_CheckLxmlLibraryVersion(void) {
         goto FINALIZE;
     }
 
-    if (PyLong_AsLong(major) != PyXmlSec_GetLibXmlVersionMajor() || PyLong_AsLong(minor) != PyXmlSec_GetLibXmlVersionMinor()) {
+    long lxml_major = PyLong_AsLong(major);
+    long lxml_minor = PyLong_AsLong(minor);
+    long xmlsec_major = PyXmlSec_GetLibXmlVersionMajor();
+    long xmlsec_minor = PyXmlSec_GetLibXmlVersionMinor();
+
+    if (lxml_major != xmlsec_major || lxml_minor != xmlsec_minor) {
+        PySys_WriteStderr(
+            "python-xmlsec: lxml libxml2 version %ld.%ld differs from xmlsec libxml2 version %ld.%ld\n",
+            lxml_major,
+            lxml_minor,
+            xmlsec_major,
+            xmlsec_minor
+        );
         goto FINALIZE;
     }