fix regex to detect valgrind version

New PCRE version got stricter

run-tests.php

@@ -581,7 +581,7 @@ function save_or_mail_results()
 					if (!$valgrind_header) {
 						error("Valgrind returned no version info, cannot proceed.\nPlease check if Valgrind is installed.");
 					} else {
-						$valgrind_version = preg_replace("/valgrind-([0-9])\.([0-9])\.([0-9]+)([.-\w]+)?(\s+)/", '$1$2$3', $valgrind_header, 1, $replace_count);
+						$valgrind_version = preg_replace("/valgrind-(\d)\.(\d)\.(\d+)([.\w_-]+)?(\s+)/", '$1$2$3', $valgrind_header, 1, $replace_count);
 						if ($replace_count != 1 || !is_numeric($valgrind_version)) {
 							error("Valgrind returned invalid version info (\"$valgrind_header\"), cannot proceed.");
 						}