reenabling avx under vs (#644)

src/isadetection.c

@@ -48,15 +48,15 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <stdint.h>
 #include <stdlib.h>
 
-// Binaries produced by Visual Studio with solely AVX2 routines
+// Binaries produced by Visual Studio 19.38 with solely AVX2 routines
 // can compile to AVX-512 thus causing crashes on non-AVX-512 systems.
 // This appears to affect VS 17.8 and 17.9. We disable AVX-512 and AVX2
 // on these systems. It seems that ClangCL is not affected.
 // https://github.com/RoaringBitmap/CRoaring/pull/603
 #ifndef __clang__
-#if _MSC_VER >= 1938
+#if _MSC_VER == 1938
 #define ROARING_DISABLE_AVX 1
-#endif  // _MSC_VER >= 1938
+#endif  // _MSC_VER == 1938
 #endif  // __clang__
 
 // We need portability.h to be included first, see