diff --git a/lib/libm/libm.h b/lib/libm/libm.h
index f782249e53465..78de4c3ee4b0f 100644
--- a/lib/libm/libm.h
+++ b/lib/libm/libm.h
@@ -19,7 +19,10 @@
 #include <stdint.h>
 #include <math.h>
 
-#define FLT_EVAL_METHOD 0
+// These lines verify that FLT_EVAL_METHOD==0, MicroPython's libm requires this.
+// If compilation fails here then check the host compiler's FLT_EVAL_METHOD.
+typedef float float_t;
+typedef double double_t;
 
 #define FORCE_EVAL(x) do {                        \
 	if (sizeof(x) == sizeof(float)) {         \
diff --git a/lib/libm_dbl/libm.h b/lib/libm_dbl/libm.h
index dc0b431a44857..cbae6916625e2 100644
--- a/lib/libm_dbl/libm.h
+++ b/lib/libm_dbl/libm.h
@@ -15,7 +15,10 @@
 #include <stdint.h>
 #include <math.h>
 
-#define FLT_EVAL_METHOD 0
+// These lines verify that FLT_EVAL_METHOD==0, MicroPython's libm requires this.
+// If compilation fails here then check the host compiler's FLT_EVAL_METHOD.
+typedef float float_t;
+typedef double double_t;
 
 #define FORCE_EVAL(x) do {                        \
 	if (sizeof(x) == sizeof(float)) {         \