Issue #13545: Fix platform.libc_version() is the SO version is missing

diff --git a/Lib/platform.py b/Lib/platform.py
index 6e301da0e17960fd16e666c16ad80ba51e4a49c7..e04bcb4ef6338a1d42b7c79f0c37efd86f8e551f 100755 (executable)
--- a/Lib/platform.py
+++ b/Lib/platform.py
@@ -181,7 +181,7 @@ def libc_ver(executable=sys.executable,lib='',version='',
         elif so:
             if lib != 'glibc':
                 lib = 'libc'
-                if soversion > version:
+                if soversion and soversion > version:
                     version = soversion
                 if threads and version[-len(threads):] != threads:
                     version = version + threads