PL_perlio_mutex is only needed with USE_UIHREADS && USE_PERLIO

(Not that Configure will let you configure with ithreads but without perlio)

diff --git a/perlvars.h b/perlvars.h
index e82f03a..a92a0a0 100644 (file)
--- a/perlvars.h
+++ b/perlvars.h
@@ -131,7 +131,7 @@ PERLVARI(Gmy_cxt_index, int, 0)
 PERLVAR(Ghints_mutex, perl_mutex)    /* Mutex for refcounted he refcounting */
 #endif
 
-#if defined(USE_ITHREADS)
+#if defined(USE_ITHREADS) && defined(USE_PERLIO)
 PERLVAR(Gperlio_mutex, perl_mutex)    /* Mutex for perlio fd refcounts */
 #endif