diff --git a/src/blan/b_soc.h b/src/blan/b_soc.h
index 1e400554c..9fb62cc68 100644
--- a/src/blan/b_soc.h
+++ b/src/blan/b_soc.h
@@ -10,10 +10,18 @@
 #ifndef __B_SOC__
 #define __B_SOC__
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include "../doomstat.h"
 #include "../deh_soc.h"
 
 boolean B_UseWallTransfer(void);
 boolean B_UseTerrainDef(void);
 
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
 #endif