diff --git a/cc3200/mpconfigport.h b/cc3200/mpconfigport.h
index fbf227b86e30e5a6c39c7555e7fe08319ee41197..331db8100e39ee8e89e5b29217ae894e01248f85 100644
--- a/cc3200/mpconfigport.h
+++ b/cc3200/mpconfigport.h
@@ -198,14 +198,6 @@ typedef long            mp_off_t;
 // disabling/enabling and sleep mode enter/exit
 #include "cc3200_asm.h"
 
-// There is no classical C heap in bare-metal ports, only Python
-// garbage-collected heap. For completeness, emulate C heap via
-// GC heap. Note that MicroPython core never uses malloc() and friends,
-// so these defines are mostly to help extension module writers.
-#define malloc                                      gc_alloc
-#define free                                        gc_free
-#define realloc                                     gc_realloc
-
 // We need to provide a declaration/definition of alloca()
 #include <alloca.h>
 
diff --git a/teensy/mpconfigport.h b/teensy/mpconfigport.h
index 867c4e652791db89123258eda9dd31911eca611a..05c040d415d1f94f171aedde274c0e60647b6e02 100644
--- a/teensy/mpconfigport.h
+++ b/teensy/mpconfigport.h
@@ -100,14 +100,6 @@ __attribute__(( always_inline )) static inline mp_uint_t disable_irq(void) {
 #define MICROPY_BEGIN_ATOMIC_SECTION()     disable_irq()
 #define MICROPY_END_ATOMIC_SECTION(state)  enable_irq(state)
 
-// There is no classical C heap in bare-metal ports, only Python
-// garbage-collected heap. For completeness, emulate C heap via
-// GC heap. Note that MicroPython core never uses malloc() and friends,
-// so these defines are mostly to help extension module writers.
-#define malloc gc_alloc
-#define free gc_free
-#define realloc gc_realloc
-
 // We need to provide a declaration/definition of alloca()
 #include <alloca.h>