Index: uspace/lib/c/include/fibril.h
===================================================================
--- uspace/lib/c/include/fibril.h	(revision 8f466fc8601edc0d9cef7fbe25b44c0dda5b0494)
+++ uspace/lib/c/include/fibril.h	(revision 25ebfbd4eb608d82bc8db3a27ab0f3eea9a10a33)
@@ -41,7 +41,9 @@
 
 #define context_set_generic(c, _pc, stack, size, ptls) \
-	(c)->pc = (sysarg_t) (_pc); \
-	(c)->sp = ((sysarg_t) (stack)) + (size) - SP_DELTA; \
-	(c)->tls = (sysarg_t) (ptls);
+	do { \
+		(c)->pc = (sysarg_t) (_pc); \
+		(c)->sp = ((sysarg_t) (stack)) + (size) - SP_DELTA; \
+		(c)->tls = (sysarg_t) (ptls); \
+	} while (0)
 
 #define FIBRIL_SERIALIZED  1