Fix build for non-C99 compatible compilers

Cython/Utility/ModuleSetupCode.c

@@ -262,10 +262,23 @@
   #define __Pyx_DOCSTR(n)  (n)
 #endif
 
+/* inline attribute */
+#ifndef CYTHON_INLINE
+  #if defined(__GNUC__)
+    #define CYTHON_INLINE __inline__
+  #elif defined(_MSC_VER)
+    #define CYTHON_INLINE __inline
+  #elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+    #define CYTHON_INLINE inline
+  #else
+    #define CYTHON_INLINE
+  #endif
+#endif
+
 #ifdef NAN
 #define __PYX_NAN() ((float) NAN)
 #else
-static inline float __PYX_NAN() {
+static CYTHON_INLINE float __PYX_NAN() {
   /* Initialize NaN. The sign is irrelevant, an exponent with all bits 1 and
    a nonzero mantissa means NaN. If the first bit in the mantissa is 1, it is
    a quiet NaN. */
@@ -277,19 +290,6 @@ static inline float __PYX_NAN() {
 
 /////////////// UtilityFunctionPredeclarations.proto ///////////////
 
-/* inline attribute */
-#ifndef CYTHON_INLINE
-  #if defined(__GNUC__)
-    #define CYTHON_INLINE __inline__
-  #elif defined(_MSC_VER)
-    #define CYTHON_INLINE __inline
-  #elif defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
-    #define CYTHON_INLINE inline
-  #else
-    #define CYTHON_INLINE
-  #endif
-#endif
-
 /* unused attribute */
 #ifndef CYTHON_UNUSED
 # if defined(__GNUC__)