Fixed issue #31 : lz4.c warning under visual
diff --git a/lz4.c b/lz4.c
index 9345e74..198b581 100644
--- a/lz4.c
+++ b/lz4.c
@@ -289,7 +289,7 @@
/**************************************
Macros
**************************************/
-#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(!!(c)) }; } /* use only *after* variable declarations */
+#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
#if LZ4_ARCH64 || !defined(__GNUC__)
# define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); } /* at the end, d>=e; */
#else
