Fix noinline definition so that it works for more compilers.

src/util.h

@@ -43,6 +43,23 @@ static const int64 CENT = 1000000;
 #define ARRAYLEN(array)     (sizeof(array)/sizeof((array)[0]))
 #define printf              OutputDebugStringF
 
+// Unfortunately there's no standard way of preventing a function from being
+// inlined, so we define a macro for it.
+//
+// You should use it like this:
+//   NOINLINE void function() {...}
+#if defined(__GNUC__)
+// This also works and will be defined for any compiler implementing gcc
+// extensions, such as clang and icc.
+#define NOINLINE __attribute__((noinline))
+#elif defined(_MSC_VER)
+#define NOINLINE __declspec(noinline)
+#else
+// We give out a warning because it impacts the correctness of one bignum test.
+#warning You should define NOINLINE for your compiler.
+#define NOINLINE
+#endif
+
 #ifdef snprintf
 #undef snprintf
 #endif