diff --git a/drivers/dht/dht.py b/drivers/dht/dht.py
deleted file mode 100644
index eed61df7c9..0000000000
--- a/drivers/dht/dht.py
+++ /dev/null
@@ -1,35 +0,0 @@
-# DHT11/DHT22 driver for MicroPython on ESP8266
-# MIT license; Copyright (c) 2016 Damien P. George
-
-try:
-    from esp import dht_readinto
-except:
-    from pyb import dht_readinto
-
-class DHTBase:
-    def __init__(self, pin):
-        self.pin = pin
-        self.buf = bytearray(5)
-
-    def measure(self):
-        buf = self.buf
-        dht_readinto(self.pin, buf)
-        if (buf[0] + buf[1] + buf[2] + buf[3]) & 0xff != buf[4]:
-            raise Exception("checksum error")
-
-class DHT11(DHTBase):
-    def humidity(self):
-        return self.buf[0]
-
-    def temperature(self):
-        return self.buf[2]
-
-class DHT22(DHTBase):
-    def humidity(self):
-        return (self.buf[0] << 8 | self.buf[1]) * 0.1
-
-    def temperature(self):
-        t = ((self.buf[2] & 0x7f) << 8 | self.buf[3]) * 0.1
-        if self.buf[2] & 0x80:
-            t = -t
-        return t
diff --git a/extmod/modwebrepl.c b/extmod/modwebrepl.c
index 48b49bfc4f..06da210d15 100644
--- a/extmod/modwebrepl.c
+++ b/extmod/modwebrepl.c
@@ -37,7 +37,7 @@
 #include "extmod/modwebsocket.h"
 #include "genhdr/mpversion.h"
 
-#ifdef MICROPY_PY_WEBREPL
+#if MICROPY_PY_WEBREPL
 
 #if 0 // print debugging info
 #define DEBUG_printf DEBUG_printf
diff --git a/extmod/uos_dupterm.c b/extmod/uos_dupterm.c
index 0de26cbdd4..cc6d97f419 100644
--- a/extmod/uos_dupterm.c
+++ b/extmod/uos_dupterm.c
@@ -34,7 +34,7 @@
 #include "py/stream.h"
 #include "lib/utils/interrupt_char.h"
 
-#ifdef MICROPY_PY_OS_DUPTERM
+#if MICROPY_PY_OS_DUPTERM
 
 void mp_uos_deactivate(size_t dupterm_idx, const char *msg, mp_obj_t exc) {
     mp_obj_t term = MP_STATE_VM(dupterm_objs[dupterm_idx]);
diff --git a/extmod/vfs_posix.c b/extmod/vfs_posix.c
index 6e3bb2c5bd..9ee4900ee2 100644
--- a/extmod/vfs_posix.c
+++ b/extmod/vfs_posix.c
@@ -29,7 +29,7 @@
 #include "extmod/vfs.h"
 #include "extmod/vfs_posix.h"
 
-#if MICROPY_VFS_POSIX
+#if defined(MICROPY_VFS_POSIX) && MICROPY_VFS_POSIX
 
 #include <string.h>
 #include <sys/stat.h>
diff --git a/extmod/vfs_posix.h b/extmod/vfs_posix.h
index 00756b4c9d..32299b8269 100644
--- a/extmod/vfs_posix.h
+++ b/extmod/vfs_posix.h
@@ -27,6 +27,7 @@
 #define MICROPY_INCLUDED_EXTMOD_VFS_POSIX_H
 
 #include "py/lexer.h"
+#include "py/mpconfig.h"
 #include "py/obj.h"
 
 extern const mp_obj_type_t mp_type_vfs_posix;
diff --git a/extmod/vfs_posix_file.c b/extmod/vfs_posix_file.c
index 435ac65cd4..d3ed4fe217 100644
--- a/extmod/vfs_posix_file.c
+++ b/extmod/vfs_posix_file.c
@@ -28,7 +28,7 @@
 #include "py/stream.h"
 #include "extmod/vfs_posix.h"
 
-#if MICROPY_VFS_POSIX
+#if defined(MICROPY_VFS_POSIX) && MICROPY_VFS_POSIX
 
 #include <fcntl.h>
 
diff --git a/py/asmarm.h b/py/asmarm.h
index fbfe09aacd..5603030912 100644
--- a/py/asmarm.h
+++ b/py/asmarm.h
@@ -122,7 +122,7 @@ void asm_arm_bcc_label(asm_arm_t *as, int cond, uint label);
 void asm_arm_b_label(asm_arm_t *as, uint label);
 void asm_arm_bl_ind(asm_arm_t *as, void *fun_ptr, uint fun_id, uint reg_temp);
 
-#ifdef GENERIC_ASM_API
+#if defined(GENERIC_ASM_API) && GENERIC_ASM_API
 
 // The following macros provide a (mostly) arch-independent API to
 // generate native code, and are used by the native emitter.
diff --git a/py/asmthumb.h b/py/asmthumb.h
index f8665f35cc..b7e2acc048 100644
--- a/py/asmthumb.h
+++ b/py/asmthumb.h
@@ -238,7 +238,7 @@ void asm_thumb_b_label(asm_thumb_t *as, uint label); // convenience: picks narro
 void asm_thumb_bcc_label(asm_thumb_t *as, int cc, uint label); // convenience: picks narrow or wide branch
 void asm_thumb_bl_ind(asm_thumb_t *as, void *fun_ptr, uint fun_id, uint reg_temp); // convenience
 
-#ifdef GENERIC_ASM_API
+#if defined(GENERIC_ASM_API) && GENERIC_ASM_API
 
 // The following macros provide a (mostly) arch-independent API to
 // generate native code, and are used by the native emitter.
diff --git a/py/asmx64.h b/py/asmx64.h
index 9ed2a6cf95..ed0b785fb2 100644
--- a/py/asmx64.h
+++ b/py/asmx64.h
@@ -114,7 +114,7 @@ void asm_x64_mov_r64_to_local(asm_x64_t* as, int src_r64, int dest_local_num);
 void asm_x64_mov_local_addr_to_r64(asm_x64_t* as, int local_num, int dest_r64);
 void asm_x64_call_ind(asm_x64_t* as, void* ptr, int temp_r32);
 
-#ifdef GENERIC_ASM_API
+#if defined(GENERIC_ASM_API) && GENERIC_ASM_API
 
 // The following macros provide a (mostly) arch-independent API to
 // generate native code, and are used by the native emitter.
diff --git a/py/asmxtensa.h b/py/asmxtensa.h
index 13d3e82346..ef80f700a3 100644
--- a/py/asmxtensa.h
+++ b/py/asmxtensa.h
@@ -239,7 +239,7 @@ void asm_xtensa_mov_local_reg(asm_xtensa_t *as, int local_num, uint reg_src);
 void asm_xtensa_mov_reg_local(asm_xtensa_t *as, uint reg_dest, int local_num);
 void asm_xtensa_mov_reg_local_addr(asm_xtensa_t *as, uint reg_dest, int local_num);
 
-#ifdef GENERIC_ASM_API
+#if defined(GENERIC_ASM_API) && GENERIC_ASM_API
 
 // The following macros provide a (mostly) arch-independent API to
 // generate native code, and are used by the native emitter.
diff --git a/py/modmath.c b/py/modmath.c
index 56ceb14bd1..4fa36d3047 100644
--- a/py/modmath.c
+++ b/py/modmath.c
@@ -26,7 +26,6 @@
 
 #include "py/builtin.h"
 #include "py/runtime.h"
-#include "py/runtime.h"
 
 #if MICROPY_PY_BUILTINS_FLOAT && MICROPY_PY_MATH
 
diff --git a/py/mpconfig.h b/py/mpconfig.h
index 52a7c05a21..d80730809d 100755
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -1238,6 +1238,22 @@ typedef double mp_float_t;
 #define MICROPY_PY_BTREE (0)
 #endif
 
+#ifndef MICROPY_PY_OS_DUPTERM
+#define MICROPY_PY_OS_DUPTERM (0)
+#endif
+
+#ifndef MICROPY_PY_LWIP_SLIP
+#define MICROPY_PY_LWIP_SLIP (0)
+#endif
+
+#ifndef MICROPY_HW_ENABLE_USB
+#define MICROPY_HW_ENABLE_USB (0)
+#endif
+
+#ifndef MICROPY_PY_WEBREPL
+#define MICROPY_PY_WEBREPL (0)
+#endif
+
 /*****************************************************************************/
 /* Hooks for a port to add builtins                                          */
 
diff --git a/py/mperrno.h b/py/mperrno.h
index 1eb342bc36..f7dad4c542 100644
--- a/py/mperrno.h
+++ b/py/mperrno.h
@@ -26,8 +26,6 @@
 #ifndef MICROPY_INCLUDED_PY_MPERRNO_H
 #define MICROPY_INCLUDED_PY_MPERRNO_H
 
-#include "py/mpconfig.h"
-
 #include "py/mpconfig.h"
 #include "py/obj.h"
 
diff --git a/py/nlr.c b/py/nlr.c
index 03d01577e1..1bfd9c19b0 100644
--- a/py/nlr.c
+++ b/py/nlr.c
@@ -28,7 +28,7 @@
 
 #if !MICROPY_NLR_SETJMP
 // When not using setjmp, nlr_push_tail is called from inline asm so needs special care
-#if MICROPY_NLR_X86 && MICROPY_NLR_OS_WINDOWS
+#if defined(MICROPY_NLR_X86) && MICROPY_NLR_X86 && defined(MICROPY_NLR_OS_WINDOWS) && MICROPY_NLR_OS_WINDOWS
 // On these 32-bit platforms make sure nlr_push_tail doesn't have a leading underscore
 unsigned int nlr_push_tail(nlr_buf_t *nlr) asm("nlr_push_tail");
 #else
diff --git a/py/nlr.h b/py/nlr.h
index 90595a12d3..802f5f39a3 100644
--- a/py/nlr.h
+++ b/py/nlr.h
@@ -35,7 +35,8 @@
 #include "py/mpconfig.h"
 
 // If MICROPY_NLR_SETJMP is not enabled then auto-detect the machine arch
-#if !MICROPY_NLR_SETJMP
+#if !defined(MICROPY_NLR_SETJMP) || !MICROPY_NLR_SETJMP
+#define MICROPY_NLR_SETJMP (0)
 // A lot of nlr-related things need different treatment on Windows
 #if defined(_WIN32) || defined(__CYGWIN__)
 #define MICROPY_NLR_OS_WINDOWS 1
diff --git a/py/nlrx64.c b/py/nlrx64.c
index a3a1cf341b..9b2b22c225 100644
--- a/py/nlrx64.c
+++ b/py/nlrx64.c
@@ -26,7 +26,7 @@
 
 #include "py/mpstate.h"
 
-#if MICROPY_NLR_X64
+#if defined(MICROPY_NLR_X64) && MICROPY_NLR_X64
 
 #undef nlr_push
 
diff --git a/py/nlrx86.c b/py/nlrx86.c
index 59b97d8ee6..4900a4c0d2 100644
--- a/py/nlrx86.c
+++ b/py/nlrx86.c
@@ -26,14 +26,14 @@
 
 #include "py/mpstate.h"
 
-#if MICROPY_NLR_X86
+#if defined(MICROPY_NLR_X86) && MICROPY_NLR_X86
 
 #undef nlr_push
 
 // For reference, x86 callee save regs are:
 //  ebx, esi, edi, ebp, esp, eip
 
-#if MICROPY_NLR_OS_WINDOWS
+#if defined(MICROPY_NLR_OS_WINDOWS) && MICROPY_NLR_OS_WINDOWS
 unsigned int nlr_push_tail(nlr_buf_t *nlr) asm("nlr_push_tail");
 #else
 __attribute__((used)) unsigned int nlr_push_tail(nlr_buf_t *nlr);
diff --git a/py/nlrxtensa.c b/py/nlrxtensa.c
index cd3dee364c..d66c7a9a7f 100644
--- a/py/nlrxtensa.c
+++ b/py/nlrxtensa.c
@@ -26,7 +26,7 @@
 
 #include "py/mpstate.h"
 
-#if MICROPY_NLR_XTENSA
+#if defined(MICROPY_NLR_XTENSA) && MICROPY_NLR_XTENSA
 
 #undef nlr_push
 
diff --git a/py/obj.h b/py/obj.h
index 42c88ef67f..040c8630de 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -526,6 +526,8 @@ struct _mp_obj_type_t {
 extern const mp_obj_type_t mp_type_type;
 extern const mp_obj_type_t mp_type_object;
 extern const mp_obj_type_t mp_type_NoneType;
+extern const mp_obj_type_t mp_type_bool;
+extern const mp_obj_type_t mp_type_int;
 extern const mp_obj_type_t mp_type_str;
 extern const mp_obj_type_t mp_type_bytes;
 extern const mp_obj_type_t mp_type_bytearray;
diff --git a/py/objtype.c b/py/objtype.c
index dc9724e5b3..7244abd9e2 100644
--- a/py/objtype.c
+++ b/py/objtype.c
@@ -1283,7 +1283,8 @@ STATIC void super_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
                 attr_get_method[2] = self_in;
                 attr_get_method[3] = MP_OBJ_FROM_PTR(mp_obj_get_type(self_in));
                 dest[0] = mp_call_method_n_kw(2, 0, attr_get_method);
-        }
+            }
+            #endif
         return;
     }
 
diff --git a/py/parse.c b/py/parse.c
index ab162710d7..f915f7598b 100644
--- a/py/parse.c
+++ b/py/parse.c
@@ -190,7 +190,7 @@ static const size_t FIRST_RULE_WITH_OFFSET_ABOVE_255 =
 #undef DEF_RULE_NC
 0;
 
-#if USE_RULE_NAME
+#if defined(USE_RULE_NAME) && USE_RULE_NAME
 // Define an array of rule names corresponding to each rule
 STATIC const char *const rule_name_table[] = {
 #define DEF_RULE(rule, comp, kind, ...) #rule,
@@ -403,7 +403,7 @@ void mp_parse_node_print(mp_parse_node_t pn, size_t indent) {
             #endif
         } else {
             size_t n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
-            #if USE_RULE_NAME
+            #if defined(USE_RULE_NAME) && USE_RULE_NAME
             printf("%s(%u) (n=%u)\n", rule_name_table[MP_PARSE_NODE_STRUCT_KIND(pns)], (uint)MP_PARSE_NODE_STRUCT_KIND(pns), (uint)n);
             #else
             printf("rule(%u) (n=%u)\n", (uint)MP_PARSE_NODE_STRUCT_KIND(pns), (uint)n);