rts: IPE.c: don't do mutex stuff when THREADED_RTS is not defined

This patch adds the missing THREADED_RTS CPP guard to mutex logic in
IPE.c.

1 files changed, 10 insertions, 0 deletions

diff --git a/rts/IPE.c b/rts/IPE.c
index 8e4664d72e..63df8be700 100644
--- a/rts/IPE.c
+++ b/rts/IPE.c
@@ -63,10 +63,20 @@ static HashTable *ipeMap = NULL;
 // Accessed atomically
 static IpeBufferListNode *ipeBufferList = NULL;
 
+#if defined(THREADED_RTS)
+
 void initIpe(void) { initMutex(&ipeMapLock); }
 
 void exitIpe(void) { closeMutex(&ipeMapLock); }
 
+#else
+
+void initIpe(void) { }
+
+void exitIpe(void) { }
+
+#endif // THREADED_RTS
+
 static InfoProvEnt ipeBufferEntryToIpe(const IpeBufferListNode *node, const IpeBufferEntry *ent)
 {
     const char *strings = node->string_table;