Fix up FC_LIKELY macros
__builtin_expect returns the same type as the expression,
so enforce that we pass in a boolean expression.
Pointed out by Emmanuele Bassi.
diff --git a/src/fcint.h b/src/fcint.h
index fb173b5..a3b192d 100644
--- a/src/fcint.h
+++ b/src/fcint.h
@@ -61,8 +61,8 @@
#define FC_LIKELY(expr) (expr)
#define FC_UNLIKELY(expr) (expr)
#else
-#define FC_LIKELY(expr) (__builtin_expect (expr, 1))
-#define FC_UNLIKELY(expr) (__builtin_expect (expr, 0))
+#define FC_LIKELY(expr) (__builtin_expect (((expr) ? 1 : 0), 1))
+#define FC_UNLIKELY(expr) (__builtin_expect (((expr) ? 1 : 0), 0))
#endif
#ifdef _WIN32
