1 files changed, 7 insertions, 0 deletions
diff --git a/py/objfloat.c b/py/objfloat.c
index 5c90b1491c..0728fce315 100644
--- a/py/objfloat.c
+++ b/py/objfloat.c
@@ -47,6 +47,13 @@
 #define M_PI (3.14159265358979323846)
 #endif
 
+// Workaround a bug in recent MSVC where NAN is no longer constant.
+// (By redefining back to the previous MSVC definition of NAN)
+#if defined(_MSC_VER) && _MSC_VER >= 1942
+#undef NAN
+#define NAN (-(float)(((float)(1e+300 * 1e+300)) * 0.0F))
+#endif
+
 typedef struct _mp_obj_float_t {
     mp_obj_base_t base;
     mp_float_t value;