diff --git a/bare-arm/Makefile b/bare-arm/Makefile
index 745945deb6..ed8c00482b 100644
--- a/bare-arm/Makefile
+++ b/bare-arm/Makefile
@@ -13,7 +13,7 @@ INC += -I$(PY_SRC)
 INC += -I$(BUILD)
 
 CFLAGS_CORTEX_M4 = -mthumb -mtune=cortex-m4 -mabi=aapcs-linux -mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=hard -fsingle-precision-constant -Wdouble-promotion
-CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 $(CFLAGS_CORTEX_M4) $(COPT)
+CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 -nostdlib $(CFLAGS_CORTEX_M4) $(COPT)
 
 #Debugging/Optimization
 ifeq ($(DEBUG), 1)
@@ -22,7 +22,7 @@ else
 CFLAGS += -Os -DNDEBUG
 endif
 
-LDFLAGS = --nostdlib -T stm32f405.ld
+LDFLAGS = -nostdlib -T stm32f405.ld
 LIBS =
 
 SRC_C = \
diff --git a/py/asmthumb.c b/py/asmthumb.c
index 891947567b..03752ed938 100644
--- a/py/asmthumb.c
+++ b/py/asmthumb.c
@@ -28,8 +28,8 @@
 #include <assert.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "asmthumb.h"
 
 // wrapper around everything in this file
diff --git a/py/asmx64.c b/py/asmx64.c
index 6c22ea25de..4695bdc731 100644
--- a/py/asmx64.c
+++ b/py/asmx64.c
@@ -29,8 +29,8 @@
 #include <assert.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 
 // wrapper around everything in this file
 #if MICROPY_EMIT_X64
diff --git a/py/binary.c b/py/binary.c
index 833d9c85ad..9eab01c4eb 100644
--- a/py/binary.c
+++ b/py/binary.c
@@ -29,8 +29,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "binary.h"
diff --git a/py/builtin.c b/py/builtin.c
index 834108f1b5..d4b77d37a8 100644
--- a/py/builtin.c
+++ b/py/builtin.c
@@ -113,10 +113,12 @@ mp_obj_t mp_builtin_abs(mp_obj_t o_in) {
         } else {
             return o_in;
         }
+#if MICROPY_PY_BUILTINS_COMPLEX
     } else if (MP_OBJ_IS_TYPE(o_in, &mp_type_complex)) {
         mp_float_t real, imag;
         mp_obj_complex_get(o_in, &real, &imag);
         return mp_obj_new_float(MICROPY_FLOAT_C_FUN(sqrt)(real*real + imag*imag));
+#endif
 #endif
     } else {
         assert(0);
@@ -154,7 +156,7 @@ MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_any_obj, mp_builtin_any);
 
 STATIC mp_obj_t mp_builtin_bin(mp_obj_t o_in) {
     mp_obj_t args[] = { MP_OBJ_NEW_QSTR(MP_QSTR__brace_open__colon__hash_b_brace_close_), o_in };
-    return mp_obj_str_format(ARRAY_SIZE(args), args);
+    return mp_obj_str_format(MP_ARRAY_SIZE(args), args);
 }
 
 MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_bin_obj, mp_builtin_bin);
diff --git a/py/builtintables.c b/py/builtintables.c
index 857a581de4..8b4df93177 100644
--- a/py/builtintables.c
+++ b/py/builtintables.c
@@ -26,8 +26,8 @@
 
 #include <stdlib.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -44,7 +44,7 @@ STATIC const mp_map_elem_t mp_builtin_object_table[] = {
     { MP_OBJ_NEW_QSTR(MP_QSTR_bool), (mp_obj_t)&mp_type_bool },
     { MP_OBJ_NEW_QSTR(MP_QSTR_bytes), (mp_obj_t)&mp_type_bytes },
     { MP_OBJ_NEW_QSTR(MP_QSTR_bytearray), (mp_obj_t)&mp_type_bytearray },
-#if MICROPY_PY_BUILTINS_FLOAT
+#if MICROPY_PY_BUILTINS_COMPLEX
     { MP_OBJ_NEW_QSTR(MP_QSTR_complex), (mp_obj_t)&mp_type_complex },
 #endif
     { MP_OBJ_NEW_QSTR(MP_QSTR_dict), (mp_obj_t)&mp_type_dict },
@@ -150,8 +150,8 @@ const mp_obj_dict_t mp_builtin_object_dict_obj = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_builtin_object_table),
-        .alloc = ARRAY_SIZE(mp_builtin_object_table),
+        .used = MP_ARRAY_SIZE(mp_builtin_object_table),
+        .alloc = MP_ARRAY_SIZE(mp_builtin_object_table),
         .table = (mp_map_elem_t*)mp_builtin_object_table,
     },
 };
@@ -195,8 +195,8 @@ const mp_obj_dict_t mp_builtin_module_dict_obj = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_builtin_module_table),
-        .alloc = ARRAY_SIZE(mp_builtin_module_table),
+        .used = MP_ARRAY_SIZE(mp_builtin_module_table),
+        .alloc = MP_ARRAY_SIZE(mp_builtin_module_table),
         .table = (mp_map_elem_t*)mp_builtin_module_table,
     },
 };
diff --git a/py/compile.c b/py/compile.c
index 946c8924b2..d49edd6ef3 100644
--- a/py/compile.c
+++ b/py/compile.c
@@ -31,8 +31,8 @@
 #include <assert.h>
 #include <math.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
@@ -111,8 +111,8 @@ STATIC const mp_map_elem_t mp_constants_table[] = {
 STATIC const mp_map_t mp_constants_map = {
     .all_keys_are_qstrs = 1,
     .table_is_fixed_array = 1,
-    .used = ARRAY_SIZE(mp_constants_table),
-    .alloc = ARRAY_SIZE(mp_constants_table),
+    .used = MP_ARRAY_SIZE(mp_constants_table),
+    .alloc = MP_ARRAY_SIZE(mp_constants_table),
     .table = (mp_map_elem_t*)mp_constants_table,
 };
 
diff --git a/py/emitbc.c b/py/emitbc.c
index 841dd4aabb..3eb0d575b9 100644
--- a/py/emitbc.c
+++ b/py/emitbc.c
@@ -30,8 +30,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/emitcommon.c b/py/emitcommon.c
index ea65183623..4649793134 100644
--- a/py/emitcommon.c
+++ b/py/emitcommon.c
@@ -28,8 +28,8 @@
 #include <stdint.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/emitcpy.c b/py/emitcpy.c
index a8a6265b8c..fbca3805b3 100644
--- a/py/emitcpy.c
+++ b/py/emitcpy.c
@@ -30,8 +30,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/emitglue.c b/py/emitglue.c
index f9b9460837..17dc8f867c 100644
--- a/py/emitglue.c
+++ b/py/emitglue.c
@@ -30,8 +30,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "runtime0.h"
diff --git a/py/emitinlinethumb.c b/py/emitinlinethumb.c
index 79ed1c4a02..435e1b64d9 100644
--- a/py/emitinlinethumb.c
+++ b/py/emitinlinethumb.c
@@ -30,8 +30,8 @@
 #include <stdarg.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
@@ -167,7 +167,7 @@ STATIC uint get_arg_reg(emit_inline_asm_t *emit, const char *op, mp_parse_node_t
     if (MP_PARSE_NODE_IS_ID(pn)) {
         qstr reg_qstr = MP_PARSE_NODE_LEAF_ARG(pn);
         const char *reg_str = qstr_str(reg_qstr);
-        for (uint i = 0; i < ARRAY_SIZE(reg_name_table); i++) {
+        for (uint i = 0; i < MP_ARRAY_SIZE(reg_name_table); i++) {
             const reg_name_t *r = &reg_name_table[i];
             if (reg_str[0] == r->name[0] && reg_str[1] == r->name[1] && reg_str[2] == r->name[2] && (reg_str[2] == '\0' || reg_str[3] == '\0')) {
                 if (r->reg > max_reg) {
@@ -286,7 +286,7 @@ STATIC void emit_inline_thumb_op(emit_inline_asm_t *emit, qstr op, int n_args, m
             asm_thumb_b_n(emit->as, label_num);
         } else if (op_str[0] == 'b' && op_len == 3) {
             uint cc = -1;
-            for (uint i = 0; i < ARRAY_SIZE(cc_name_table); i++) {
+            for (uint i = 0; i < MP_ARRAY_SIZE(cc_name_table); i++) {
                 if (op_str[1] == cc_name_table[i].name[0] && op_str[2] == cc_name_table[i].name[1]) {
                     cc = cc_name_table[i].cc;
                 }
diff --git a/py/emitnative.c b/py/emitnative.c
index 9a36978d0f..f291efe481 100644
--- a/py/emitnative.c
+++ b/py/emitnative.c
@@ -48,8 +48,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/emitpass1.c b/py/emitpass1.c
index 2e76420a21..bea1af4dbf 100644
--- a/py/emitpass1.c
+++ b/py/emitpass1.c
@@ -28,8 +28,8 @@
 #include <stdint.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/gc.c b/py/gc.c
index 30bae5054a..65bfea0b35 100644
--- a/py/gc.c
+++ b/py/gc.c
@@ -33,7 +33,6 @@
 #include "misc.h"
 #include "gc.h"
 
-#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "runtime.h"
@@ -113,7 +112,7 @@ STATIC machine_uint_t gc_lock_depth;
 void gc_init(void *start, void *end) {
     // align end pointer on block boundary
     end = (void*)((machine_uint_t)end & (~(BYTES_PER_BLOCK - 1)));
-    DEBUG_printf("Initializing GC heap: %p..%p = " UINT_FMT " bytes\n", start, end, end - start);
+    DEBUG_printf("Initializing GC heap: %p..%p = " UINT_FMT " bytes\n", start, end, (byte*)end - (byte*)start);
 
     // calculate parameters for GC (T=total, A=alloc table, F=finaliser table, P=pool; all in bytes):
     // T = A + F + P
@@ -268,6 +267,7 @@ STATIC void gc_sweep(void) {
 
             case AT_TAIL:
                 if (free_tail) {
+                    DEBUG_printf("gc_sweep(%p)\n",PTR_FROM_BLOCK(block));
                     ATB_ANY_TO_FREE(block);
                 }
                 break;
@@ -401,6 +401,7 @@ found:
 
     // get pointer to first block
     void *ret_ptr = (void*)(gc_pool_start + start_block * WORDS_PER_BLOCK);
+    DEBUG_printf("gc_alloc(%p)\n", ret_ptr);
 
     // zero out the additional bytes of the newly allocated blocks
     // This is needed because the blocks may have previously held pointers
@@ -439,6 +440,7 @@ void gc_free(void *ptr_in) {
     }
 
     machine_uint_t ptr = (machine_uint_t)ptr_in;
+    DEBUG_printf("gc_free(%p)\n", ptr);
 
     if (VERIFY_PTR(ptr)) {
         machine_uint_t block = BLOCK_FROM_PTR(ptr);
@@ -590,7 +592,7 @@ void *gc_realloc(void *ptr_in, machine_uint_t n_bytes) {
         return NULL;
     }
 
-    DEBUG_printf("gc_realloc: allocating new block\n");
+    DEBUG_printf("gc_realloc(%p -> %p)\n", ptr_in, ptr_out);
     memcpy(ptr_out, ptr_in, n_blocks * BYTES_PER_BLOCK);
     gc_free(ptr_in);
     return ptr_out;
diff --git a/py/lexer.c b/py/lexer.c
index a65df54ba6..5d1113fb30 100644
--- a/py/lexer.c
+++ b/py/lexer.c
@@ -32,8 +32,8 @@
 #include <stdio.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 
@@ -694,10 +694,10 @@ STATIC void mp_lexer_next_token_into(mp_lexer_t *lex, mp_token_t *tok, bool firs
         // need to check for this special token in many places in the compiler.
         // TODO improve speed of these string comparisons
         //for (int i = 0; tok_kw[i] != NULL; i++) {
-        for (int i = 0; i < ARRAY_SIZE(tok_kw); i++) {
+        for (int i = 0; i < MP_ARRAY_SIZE(tok_kw); i++) {
             if (str_strn_equal(tok_kw[i], tok->str, tok->len)) {
-                if (i == ARRAY_SIZE(tok_kw) - 1) {
-                    // tok_kw[ARRAY_SIZE(tok_kw) - 1] == "__debug__"
+                if (i == MP_ARRAY_SIZE(tok_kw) - 1) {
+                    // tok_kw[MP_ARRAY_SIZE(tok_kw) - 1] == "__debug__"
                     tok->kind = (mp_optimise_value == 0 ? MP_TOKEN_KW_TRUE : MP_TOKEN_KW_FALSE);
                 } else {
                     tok->kind = MP_TOKEN_KW_FALSE + i;
diff --git a/py/lexerstr.c b/py/lexerstr.c
index 76e90671be..666dbfa37c 100644
--- a/py/lexerstr.c
+++ b/py/lexerstr.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 
diff --git a/py/lexerunix.c b/py/lexerunix.c
index 89dc80b004..51bc915b22 100644
--- a/py/lexerunix.c
+++ b/py/lexerunix.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 
 #if MICROPY_HELPER_LEXER_UNIX
 
diff --git a/py/malloc.c b/py/malloc.c
index b180ddf6b5..8e90849e93 100644
--- a/py/malloc.c
+++ b/py/malloc.c
@@ -28,8 +28,8 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 
 #if 0 // print debugging info
 #define DEBUG_printf DEBUG_printf
diff --git a/py/map.c b/py/map.c
index 4020401622..dcc13c52cc 100644
--- a/py/map.c
+++ b/py/map.c
@@ -27,8 +27,8 @@
 #include <stdlib.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "runtime0.h"
diff --git a/py/misc.h b/py/misc.h
index 044fef6236..3f62e3198f 100644
--- a/py/misc.h
+++ b/py/misc.h
@@ -82,7 +82,7 @@ int m_get_peak_bytes_allocated(void);
 /** array helpers ***********************************************/
 
 // get the number of elements in a fixed-size array
-#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+#define MP_ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 
 /** unichar / UTF-8 *********************************************/
 
diff --git a/py/mkrules.mk b/py/mkrules.mk
index 9592d6c590..6153618fae 100644
--- a/py/mkrules.mk
+++ b/py/mkrules.mk
@@ -73,9 +73,9 @@ all: $(PROG)
 
 $(PROG): $(OBJ)
 	$(ECHO) "LINK $@"
-	$(Q)$(CC) -o $@ $(OBJ) $(LIB) $(LDFLAGS)
+	$(Q)$(CC) $(COPT) -o $@ $(OBJ) $(LIB) $(LDFLAGS)
 ifndef DEBUG
-	$(Q)$(STRIP) $(PROG)
+	$(Q)$(STRIP) $(STRIPFLAGS_EXTRA) $(PROG)
 endif
 	$(Q)$(SIZE) $(PROG)
 
diff --git a/py/modarray.c b/py/modarray.c
index a741a0ecb4..3ff567f1d9 100644
--- a/py/modarray.c
+++ b/py/modarray.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -40,8 +40,8 @@ STATIC const mp_obj_dict_t mp_module_array_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_array_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_array_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_array_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_array_globals_table),
         .table = (mp_map_elem_t*)mp_module_array_globals_table,
     },
 };
diff --git a/py/modcmath.c b/py/modcmath.c
index 3bc3055dc8..ddd8abf71e 100644
--- a/py/modcmath.c
+++ b/py/modcmath.c
@@ -26,8 +26,8 @@
 
 #include <math.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -142,8 +142,8 @@ STATIC const mp_obj_dict_t mp_module_cmath_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_cmath_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_cmath_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_cmath_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_cmath_globals_table),
         .table = (mp_map_elem_t*)mp_module_cmath_globals_table,
     },
 };
diff --git a/py/modcollections.c b/py/modcollections.c
index 9e3da7e666..5cd0b317a1 100644
--- a/py/modcollections.c
+++ b/py/modcollections.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -42,8 +42,8 @@ STATIC const mp_obj_dict_t mp_module_collections_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_collections_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_collections_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_collections_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_collections_globals_table),
         .table = (mp_map_elem_t*)mp_module_collections_globals_table,
     },
 };
diff --git a/py/modgc.c b/py/modgc.c
index c53eed235f..f136ce733d 100644
--- a/py/modgc.c
+++ b/py/modgc.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -73,8 +73,8 @@ STATIC const mp_obj_dict_t mp_module_gc_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_gc_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_gc_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_gc_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_gc_globals_table),
         .table = (mp_map_elem_t*)mp_module_gc_globals_table,
     },
 };
diff --git a/py/modio.c b/py/modio.c
index 08c6c59dd9..ef3b29b53f 100644
--- a/py/modio.c
+++ b/py/modio.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -57,8 +57,8 @@ STATIC const mp_obj_dict_t mp_module_io_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_io_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_io_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_io_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_io_globals_table),
         .table = (mp_map_elem_t*)mp_module_io_globals_table,
     },
 };
diff --git a/py/modmath.c b/py/modmath.c
index 0fd583c2ff..0d0d13b4e2 100644
--- a/py/modmath.c
+++ b/py/modmath.c
@@ -26,8 +26,8 @@
 
 #include <math.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -172,8 +172,8 @@ STATIC const mp_obj_dict_t mp_module_math_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_math_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_math_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_math_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_math_globals_table),
         .table = (mp_map_elem_t*)mp_module_math_globals_table,
     },
 };
diff --git a/py/modmicropython.c b/py/modmicropython.c
index 40d749da2d..bbb315189b 100644
--- a/py/modmicropython.c
+++ b/py/modmicropython.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -65,8 +65,8 @@ STATIC const mp_obj_dict_t mp_module_micropython_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_micropython_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_micropython_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_micropython_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_micropython_globals_table),
         .table = (mp_map_elem_t*)mp_module_micropython_globals_table,
     },
 };
diff --git a/py/modstruct.c b/py/modstruct.c
index a45181852c..2e40264e8d 100644
--- a/py/modstruct.c
+++ b/py/modstruct.c
@@ -27,8 +27,8 @@
 
 #include <assert.h>
 #include <string.h>
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -210,8 +210,8 @@ STATIC const mp_obj_dict_t mp_module_struct_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_struct_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_struct_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_struct_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_struct_globals_table),
         .table = (mp_map_elem_t*)mp_module_struct_globals_table,
     },
 };
diff --git a/py/modsys.c b/py/modsys.c
index a99db1b7f8..1e7f7eff7f 100644
--- a/py/modsys.c
+++ b/py/modsys.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "builtin.h"
@@ -87,8 +87,8 @@ STATIC const mp_obj_dict_t mp_module_sys_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_sys_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_sys_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_sys_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_sys_globals_table),
         .table = (mp_map_elem_t*)mp_module_sys_globals_table,
     },
 };
diff --git a/py/mpconfig.h b/py/mpconfig.h
index 93e98c25b6..4a3288a3d1 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -223,6 +223,10 @@ typedef double mp_float_t;
 #define MICROPY_PY_BUILTINS_FLOAT (0)
 #endif
 
+#ifndef MICROPY_PY_BUILTINS_COMPLEX
+#define MICROPY_PY_BUILTINS_COMPLEX (MICROPY_PY_BUILTINS_FLOAT)
+#endif
+
 // Enable features which improve CPython compatibility
 // but may lead to more code size/memory usage.
 // TODO: Originally intended as generic category to not
diff --git a/py/mpz.c b/py/mpz.c
index ab300b91df..3f1e859fc6 100644
--- a/py/mpz.c
+++ b/py/mpz.c
@@ -30,8 +30,8 @@
 #include <string.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "mpz.h"
 
 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
diff --git a/py/nlr.h b/py/nlr.h
index 43a0c4f6a9..cb2b53b854 100644
--- a/py/nlr.h
+++ b/py/nlr.h
@@ -29,6 +29,7 @@
 
 #include <limits.h>
 #include <setjmp.h>
+#include <assert.h>
 
 typedef struct _nlr_buf_t nlr_buf_t;
 struct _nlr_buf_t {
@@ -44,7 +45,7 @@ struct _nlr_buf_t {
   #else
     void *regs[8];
   #endif
-#elif defined(__thumb2__)
+#elif defined(__thumb2__) || defined(__thumb__) || defined(__arm__)
     void *regs[10];
 #else
     #define MICROPY_NLR_SETJMP (1)
diff --git a/py/nlrthumb.S b/py/nlrthumb.S
index b306c01753..dabf57cf85 100644
--- a/py/nlrthumb.S
+++ b/py/nlrthumb.S
@@ -24,19 +24,21 @@
  * THE SOFTWARE.
  */
 
-#if defined(__thumb2__) && !MICROPY_NLR_SETJMP
-/* thumb callee save: bx, bp, sp, r12, r14, r14, r15 */
+#if !MICROPY_NLR_SETJMP && (defined(__thumb2__) || defined(__thumb__) || defined(__arm__))
+/* arm callee save: bx, bp, sp, r12, r14, r14, r15 */
 
     .syntax unified
     /*.cpu cortex-m4*/
-    .thumb
+    /*.thumb*/
     .text
     .align  2
 
 /* uint nlr_push(r0=nlr_buf_t *nlr) */
     .global nlr_push
+#if defined(__thumb2__)
     .thumb
     .thumb_func
+#endif
     .type   nlr_push, %function
 nlr_push:
     str     lr, [r0, #8]            @ store lr into nlr_buf
@@ -64,8 +66,10 @@ nlr_push:
 
 @ void nlr_pop()
     .global nlr_pop
+#if defined(__thumb2__)
     .thumb
     .thumb_func
+#endif
     .type   nlr_pop, %function
 nlr_pop:
     ldr     r3, .L5                 @ load addr of nlr_top
@@ -80,8 +84,10 @@ nlr_pop:
 
 /* void nlr_jump(r0=uint val) */
     .global nlr_jump
+#if defined(__thumb2__)
     .thumb
     .thumb_func
+#endif
     .type   nlr_jump, %function
 nlr_jump:
     ldr     r3, .L2                 @ load addr of nlr_top
diff --git a/py/obj.c b/py/obj.c
index 6d0966db24..a0f55d65db 100644
--- a/py/obj.c
+++ b/py/obj.c
@@ -274,6 +274,7 @@ mp_float_t mp_obj_get_float(mp_obj_t arg) {
     }
 }
 
+#if MICROPY_PY_BUILTINS_COMPLEX
 void mp_obj_get_complex(mp_obj_t arg, mp_float_t *real, mp_float_t *imag) {
     if (arg == mp_const_false) {
         *real = 0;
@@ -297,6 +298,7 @@ void mp_obj_get_complex(mp_obj_t arg, mp_float_t *real, mp_float_t *imag) {
     }
 }
 #endif
+#endif
 
 void mp_obj_get_array(mp_obj_t o, uint *len, mp_obj_t **items) {
     if (MP_OBJ_IS_TYPE(o, &mp_type_tuple)) {
diff --git a/py/objcomplex.c b/py/objcomplex.c
index d58b53463c..20e7c97d37 100644
--- a/py/objcomplex.c
+++ b/py/objcomplex.c
@@ -36,7 +36,7 @@
 #include "runtime0.h"
 #include "runtime.h"
 
-#if MICROPY_PY_BUILTINS_FLOAT
+#if MICROPY_PY_BUILTINS_COMPLEX
 
 #include <math.h>
 
diff --git a/py/objenumerate.c b/py/objenumerate.c
index 7d9ea9915a..37414464de 100644
--- a/py/objenumerate.c
+++ b/py/objenumerate.c
@@ -27,8 +27,8 @@
 #include <stdlib.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "runtime.h"
@@ -45,7 +45,7 @@ STATIC const mp_arg_t enumerate_make_new_args[] = {
     { MP_QSTR_iterable, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_start, MP_ARG_INT, {.u_int = 0} },
 };
-#define ENUMERATE_MAKE_NEW_NUM_ARGS ARRAY_SIZE(enumerate_make_new_args)
+#define ENUMERATE_MAKE_NEW_NUM_ARGS MP_ARRAY_SIZE(enumerate_make_new_args)
 
 STATIC mp_obj_t enumerate_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
 #if MICROPY_CPYTHON_COMPAT
diff --git a/py/objfloat.c b/py/objfloat.c
index b608b1a3d7..e3fefad8db 100644
--- a/py/objfloat.c
+++ b/py/objfloat.c
@@ -102,9 +102,12 @@ STATIC mp_obj_t float_unary_op(int op, mp_obj_t o_in) {
 
 STATIC mp_obj_t float_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_float_t *lhs = lhs_in;
+#if MICROPY_PY_BUILTINS_COMPLEX
     if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_complex)) {
         return mp_obj_complex_binary_op(op, lhs->value, 0, rhs_in);
-    } else {
+    } else
+#endif
+    {
         return mp_obj_float_binary_op(op, lhs->value, rhs_in);
     }
 }
diff --git a/py/objint_mpz.c b/py/objint_mpz.c
index 516fb52746..cf7896f9e1 100644
--- a/py/objint_mpz.c
+++ b/py/objint_mpz.c
@@ -121,8 +121,10 @@ mp_obj_t mp_obj_int_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
 #if MICROPY_PY_BUILTINS_FLOAT
     } else if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_float)) {
         return mp_obj_float_binary_op(op, mpz_as_float(zlhs), rhs_in);
+#if MICROPY_PY_BUILTINS_COMPLEX
     } else if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_complex)) {
         return mp_obj_complex_binary_op(op, mpz_as_float(zlhs), 0, rhs_in);
+#endif
 #endif
     } else {
         // delegate to generic function to check for extra cases
diff --git a/py/parse.c b/py/parse.c
index af09c335f2..492c1678b5 100644
--- a/py/parse.c
+++ b/py/parse.c
@@ -30,8 +30,8 @@
 #include <assert.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parsenumbase.h"
diff --git a/py/parsehelper.c b/py/parsehelper.c
index 3ead5a3031..105afe711e 100644
--- a/py/parsehelper.c
+++ b/py/parsehelper.c
@@ -29,8 +29,8 @@
 #include <stdint.h>
 #include <stdio.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "lexer.h"
 #include "parse.h"
diff --git a/py/parsenum.c b/py/parsenum.c
index 1c1868ae0a..b9801ab6a1 100644
--- a/py/parsenum.c
+++ b/py/parsenum.c
@@ -27,14 +27,15 @@
 #include <stdbool.h>
 #include <stdlib.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "nlr.h"
 #include "obj.h"
 #include "parsenumbase.h"
 #include "parsenum.h"
 #include "smallint.h"
+#include "runtime.h"
 
 #if MICROPY_PY_BUILTINS_FLOAT
 #include <math.h>
@@ -252,10 +253,15 @@ mp_obj_t mp_parse_num_decimal(const char *str, uint len, bool allow_imag, bool f
     }
 
     // return the object
+#if MICROPY_PY_BUILTINS_COMPLEX
     if (imag) {
         return mp_obj_new_complex(0, dec_val);
     } else if (force_complex) {
         return mp_obj_new_complex(dec_val, 0);
+#else
+    if (imag || force_complex) {
+        mp_not_implemented("complex values not supported");
+#endif
     } else {
         return mp_obj_new_float(dec_val);
     }
diff --git a/py/parsenumbase.c b/py/parsenumbase.c
index ce140655bd..4fddac9c3d 100644
--- a/py/parsenumbase.c
+++ b/py/parsenumbase.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "parsenumbase.h"
 
 // find real radix base, and strip preceding '0x', '0o' and '0b'
diff --git a/py/pfenv.c b/py/pfenv.c
index e631f8654a..ca1e3e919b 100644
--- a/py/pfenv.c
+++ b/py/pfenv.c
@@ -27,8 +27,8 @@
 #include <stdint.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "mpz.h"
diff --git a/py/qstr.c b/py/qstr.c
index 7ccb34f1c3..10bc20ecba 100644
--- a/py/qstr.c
+++ b/py/qstr.c
@@ -27,8 +27,8 @@
 #include <assert.h>
 #include <string.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 
 // NOTE: we are using linear arrays to store and search for qstr's (unique strings, interned strings)
diff --git a/py/repl.c b/py/repl.c
index 457ce165b7..2c3dfbd4d9 100644
--- a/py/repl.c
+++ b/py/repl.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "repl.h"
 
 #if MICROPY_HELPER_REPL
diff --git a/py/runtime.c b/py/runtime.c
index d57bb686d1..b539984c0b 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -426,6 +426,7 @@ mp_obj_t mp_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
             } else {
                 return res;
             }
+#if MICROPY_PY_BUILTINS_COMPLEX
         } else if (MP_OBJ_IS_TYPE(rhs, &mp_type_complex)) {
             mp_obj_t res = mp_obj_complex_binary_op(op, lhs_val, 0, rhs);
             if (res == MP_OBJ_NULL) {
@@ -433,6 +434,7 @@ mp_obj_t mp_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
             } else {
                 return res;
             }
+#endif
 #endif
         }
     }
diff --git a/py/scope.c b/py/scope.c
index 839e8216c1..83c2b6e07c 100644
--- a/py/scope.c
+++ b/py/scope.c
@@ -29,8 +29,8 @@
 #include <stdio.h>
 #include <assert.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "parse.h"
diff --git a/py/smallint.c b/py/smallint.c
index 5543f126c3..c57f364e36 100644
--- a/py/smallint.c
+++ b/py/smallint.c
@@ -24,8 +24,8 @@
  * THE SOFTWARE.
  */
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 #include "qstr.h"
 #include "obj.h"
 #include "smallint.h"
diff --git a/py/unicode.c b/py/unicode.c
index c8faa57009..88f835131d 100644
--- a/py/unicode.c
+++ b/py/unicode.c
@@ -26,8 +26,8 @@
 
 #include <stdint.h>
 
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 
 // attribute flags
 #define FL_PRINT (0x01)
diff --git a/py/vstr.c b/py/vstr.c
index ea6a1c937f..f8b7e4dabc 100644
--- a/py/vstr.c
+++ b/py/vstr.c
@@ -29,8 +29,8 @@
 #include <stdarg.h>
 #include <string.h>
 #include <assert.h>
-#include "misc.h"
 #include "mpconfig.h"
+#include "misc.h"
 
 // returned value is always at least 1 greater than argument
 #define ROUND_ALLOC(a) (((a) & ((~0) - 7)) + 8)
diff --git a/stmhal/Makefile b/stmhal/Makefile
index e27dd7b6ce..3cc98d7be8 100644
--- a/stmhal/Makefile
+++ b/stmhal/Makefile
@@ -41,7 +41,7 @@ INC += -I$(FATFS_DIR)/src
 INC += -I$(CC3K_DIR)
 
 CFLAGS_CORTEX_M4 = -mthumb -mtune=cortex-m4 -mabi=aapcs-linux -mcpu=cortex-m4 -mfpu=fpv4-sp-d16 -mfloat-abi=hard -fsingle-precision-constant -Wdouble-promotion
-CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 $(CFLAGS_CORTEX_M4) $(COPT)
+CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 -nostdlib $(CFLAGS_CORTEX_M4) $(COPT)
 
 CFLAGS += -Iboards/$(BOARD)
 
@@ -53,7 +53,7 @@ else
 COPT += -Os -DNDEBUG
 endif
 
-LDFLAGS = --nostdlib -T stm32f405.ld -Map=$(@:.elf=.map) --cref
+LDFLAGS = -nostdlib -T stm32f405.ld -Map=$(@:.elf=.map) --cref
 LIBS =
 
 # uncomment this if you want libgcc
diff --git a/stmhal/dac.c b/stmhal/dac.c
index 81ce993a8c..725e14e906 100644
--- a/stmhal/dac.c
+++ b/stmhal/dac.c
@@ -237,7 +237,7 @@ STATIC const mp_arg_t pyb_dac_write_timed_args[] = {
     { MP_QSTR_freq, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
     { MP_QSTR_mode, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = DMA_NORMAL} },
 };
-#define PYB_DAC_WRITE_TIMED_NUM_ARGS ARRAY_SIZE(pyb_dac_write_timed_args)
+#define PYB_DAC_WRITE_TIMED_NUM_ARGS MP_ARRAY_SIZE(pyb_dac_write_timed_args)
 
 mp_obj_t pyb_dac_write_timed(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     pyb_dac_obj_t *self = args[0];
diff --git a/stmhal/extint.c b/stmhal/extint.c
index 24d51ffb8d..591246cdd1 100644
--- a/stmhal/extint.c
+++ b/stmhal/extint.c
@@ -296,7 +296,7 @@ STATIC const mp_arg_t pyb_extint_make_new_args[] = {
     { MP_QSTR_pull,     MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
     { MP_QSTR_callback, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
 };
-#define PYB_EXTINT_MAKE_NEW_NUM_ARGS ARRAY_SIZE(pyb_extint_make_new_args)
+#define PYB_EXTINT_MAKE_NEW_NUM_ARGS MP_ARRAY_SIZE(pyb_extint_make_new_args)
 
 STATIC mp_obj_t extint_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
     // type_in == extint_obj_type
diff --git a/stmhal/i2c.c b/stmhal/i2c.c
index 00501a57da..b6ab531293 100644
--- a/stmhal/i2c.c
+++ b/stmhal/i2c.c
@@ -220,7 +220,7 @@ STATIC const mp_arg_t pyb_i2c_init_args[] = {
     { MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
     { MP_QSTR_gencall,  MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
 };
-#define PYB_I2C_INIT_NUM_ARGS ARRAY_SIZE(pyb_i2c_init_args)
+#define PYB_I2C_INIT_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_init_args)
 
 STATIC mp_obj_t pyb_i2c_init_helper(const pyb_i2c_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // parse args
@@ -271,7 +271,7 @@ STATIC mp_obj_t pyb_i2c_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const
     machine_int_t i2c_id = mp_obj_get_int(args[0]) - 1;
 
     // check i2c number
-    if (!(0 <= i2c_id && i2c_id < ARRAY_SIZE(pyb_i2c_obj) && pyb_i2c_obj[i2c_id].i2c != NULL)) {
+    if (!(0 <= i2c_id && i2c_id < MP_ARRAY_SIZE(pyb_i2c_obj) && pyb_i2c_obj[i2c_id].i2c != NULL)) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "I2C bus %d does not exist", i2c_id + 1));
     }
 
@@ -363,7 +363,7 @@ STATIC const mp_arg_t pyb_i2c_send_args[] = {
     { MP_QSTR_addr,    MP_ARG_INT, {.u_int = PYB_I2C_MASTER_ADDRESS} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_I2C_SEND_NUM_ARGS ARRAY_SIZE(pyb_i2c_send_args)
+#define PYB_I2C_SEND_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_send_args)
 
 STATIC mp_obj_t pyb_i2c_send(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     pyb_i2c_obj_t *self = args[0];
@@ -414,7 +414,7 @@ STATIC const mp_arg_t pyb_i2c_recv_args[] = {
     { MP_QSTR_addr,    MP_ARG_INT, {.u_int = PYB_I2C_MASTER_ADDRESS} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_I2C_RECV_NUM_ARGS ARRAY_SIZE(pyb_i2c_recv_args)
+#define PYB_I2C_RECV_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_recv_args)
 
 STATIC mp_obj_t pyb_i2c_recv(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     pyb_i2c_obj_t *self = args[0];
@@ -470,7 +470,7 @@ STATIC const mp_arg_t pyb_i2c_mem_read_args[] = {
     { MP_QSTR_memaddr, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_I2C_MEM_READ_NUM_ARGS ARRAY_SIZE(pyb_i2c_mem_read_args)
+#define PYB_I2C_MEM_READ_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_mem_read_args)
 
 STATIC mp_obj_t pyb_i2c_mem_read(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     pyb_i2c_obj_t *self = args[0];
diff --git a/stmhal/led.c b/stmhal/led.c
index e23b30ab75..c1b298b179 100644
--- a/stmhal/led.c
+++ b/stmhal/led.c
@@ -61,7 +61,7 @@ STATIC const pyb_led_obj_t pyb_led_obj[] = {
 #endif
 #endif
 };
-#define NUM_LEDS ARRAY_SIZE(pyb_led_obj)
+#define NUM_LEDS MP_ARRAY_SIZE(pyb_led_obj)
 
 void led_init(void) {
     /* GPIO structure */
diff --git a/stmhal/main.c b/stmhal/main.c
index 9751dcac2e..e264fdf4b3 100644
--- a/stmhal/main.c
+++ b/stmhal/main.c
@@ -308,7 +308,7 @@ soft_reset:
             MP_OBJ_NEW_SMALL_INT(115200),
         };
         pyb_uart_global_debug = pyb_uart_type.make_new((mp_obj_t)&pyb_uart_type,
-                                                       ARRAY_SIZE(args),
+                                                       MP_ARRAY_SIZE(args),
                                                        0, args);
     }
 #else
diff --git a/stmhal/modos.c b/stmhal/modos.c
index 4a6949a844..e0df05ca6b 100644
--- a/stmhal/modos.c
+++ b/stmhal/modos.c
@@ -194,8 +194,8 @@ STATIC const mp_obj_dict_t os_module_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(os_module_globals_table),
-        .alloc = ARRAY_SIZE(os_module_globals_table),
+        .used = MP_ARRAY_SIZE(os_module_globals_table),
+        .alloc = MP_ARRAY_SIZE(os_module_globals_table),
         .table = (mp_map_elem_t*)os_module_globals_table,
     },
 };
diff --git a/stmhal/modpyb.c b/stmhal/modpyb.c
index 6879a2c1b7..9dcd0e76ca 100644
--- a/stmhal/modpyb.c
+++ b/stmhal/modpyb.c
@@ -426,8 +426,8 @@ STATIC const mp_obj_dict_t pyb_module_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(pyb_module_globals_table),
-        .alloc = ARRAY_SIZE(pyb_module_globals_table),
+        .used = MP_ARRAY_SIZE(pyb_module_globals_table),
+        .alloc = MP_ARRAY_SIZE(pyb_module_globals_table),
         .table = (mp_map_elem_t*)pyb_module_globals_table,
     },
 };
diff --git a/stmhal/modstm.c b/stmhal/modstm.c
index 520c8e51bd..1196ff82ff 100644
--- a/stmhal/modstm.c
+++ b/stmhal/modstm.c
@@ -131,8 +131,8 @@ STATIC const mp_obj_dict_t stm_module_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(stm_module_globals_table),
-        .alloc = ARRAY_SIZE(stm_module_globals_table),
+        .used = MP_ARRAY_SIZE(stm_module_globals_table),
+        .alloc = MP_ARRAY_SIZE(stm_module_globals_table),
         .table = (mp_map_elem_t*)stm_module_globals_table,
     },
 };
diff --git a/stmhal/modtime.c b/stmhal/modtime.c
index 4fbee31293..ea4e3210a6 100644
--- a/stmhal/modtime.c
+++ b/stmhal/modtime.c
@@ -122,8 +122,8 @@ STATIC const mp_obj_dict_t time_module_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(time_module_globals_table),
-        .alloc = ARRAY_SIZE(time_module_globals_table),
+        .used = MP_ARRAY_SIZE(time_module_globals_table),
+        .alloc = MP_ARRAY_SIZE(time_module_globals_table),
         .table = (mp_map_elem_t*)time_module_globals_table,
     },
 };
diff --git a/stmhal/spi.c b/stmhal/spi.c
index 10ecf7ec8e..448b8696ea 100644
--- a/stmhal/spi.c
+++ b/stmhal/spi.c
@@ -188,7 +188,7 @@ STATIC const pyb_spi_obj_t pyb_spi_obj[] = {
     {{&pyb_spi_type}, NULL},
 #endif
 };
-#define PYB_NUM_SPI ARRAY_SIZE(pyb_spi_obj)
+#define PYB_NUM_SPI MP_ARRAY_SIZE(pyb_spi_obj)
 
 STATIC void pyb_spi_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
     pyb_spi_obj_t *self = self_in;
@@ -242,7 +242,7 @@ STATIC const mp_arg_t pyb_spi_init_args[] = {
     { MP_QSTR_ti,       MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
     { MP_QSTR_crc,      MP_ARG_KW_ONLY | MP_ARG_OBJ,  {.u_obj = mp_const_none} },
 };
-#define PYB_SPI_INIT_NUM_ARGS ARRAY_SIZE(pyb_spi_init_args)
+#define PYB_SPI_INIT_NUM_ARGS MP_ARRAY_SIZE(pyb_spi_init_args)
 
 STATIC mp_obj_t pyb_spi_init_helper(const pyb_spi_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // parse args
@@ -359,7 +359,7 @@ STATIC const mp_arg_t pyb_spi_send_args[] = {
     { MP_QSTR_send,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_SPI_SEND_NUM_ARGS ARRAY_SIZE(pyb_spi_send_args)
+#define PYB_SPI_SEND_NUM_ARGS MP_ARRAY_SIZE(pyb_spi_send_args)
 
 STATIC mp_obj_t pyb_spi_send(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // TODO assumes transmission size is 8-bits wide
@@ -401,7 +401,7 @@ STATIC const mp_arg_t pyb_spi_recv_args[] = {
     { MP_QSTR_recv,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_SPI_RECV_NUM_ARGS ARRAY_SIZE(pyb_spi_recv_args)
+#define PYB_SPI_RECV_NUM_ARGS MP_ARRAY_SIZE(pyb_spi_recv_args)
 
 STATIC mp_obj_t pyb_spi_recv(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // TODO assumes transmission size is 8-bits wide
@@ -449,7 +449,7 @@ STATIC const mp_arg_t pyb_spi_send_recv_args[] = {
     { MP_QSTR_recv,    MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_SPI_SEND_RECV_NUM_ARGS ARRAY_SIZE(pyb_spi_send_recv_args)
+#define PYB_SPI_SEND_RECV_NUM_ARGS MP_ARRAY_SIZE(pyb_spi_send_recv_args)
 
 STATIC mp_obj_t pyb_spi_send_recv(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // TODO assumes transmission size is 8-bits wide
diff --git a/stmhal/timer.c b/stmhal/timer.c
index 0ba24754b2..ec0c4dec4c 100644
--- a/stmhal/timer.c
+++ b/stmhal/timer.c
@@ -105,7 +105,7 @@ static uint32_t tim3_counter = 0;
 
 // Used to do callbacks to Python code on interrupt
 STATIC pyb_timer_obj_t *pyb_timer_obj_all[14];
-#define PYB_TIMER_OBJ_ALL_NUM ARRAY_SIZE(pyb_timer_obj_all)
+#define PYB_TIMER_OBJ_ALL_NUM MP_ARRAY_SIZE(pyb_timer_obj_all)
 
 void timer_init0(void) {
     tim3_counter = 0;
@@ -234,7 +234,7 @@ STATIC const mp_arg_t pyb_timer_init_args[] = {
     { MP_QSTR_mode,      MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = TIM_COUNTERMODE_UP} },
     { MP_QSTR_div,       MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = TIM_CLOCKDIVISION_DIV1} },
 };
-#define PYB_TIMER_INIT_NUM_ARGS ARRAY_SIZE(pyb_timer_init_args)
+#define PYB_TIMER_INIT_NUM_ARGS MP_ARRAY_SIZE(pyb_timer_init_args)
 
 STATIC mp_obj_t pyb_timer_init_helper(pyb_timer_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // parse args
diff --git a/stmhal/uart.c b/stmhal/uart.c
index 5bbd9f299e..a85f7f9e3a 100644
--- a/stmhal/uart.c
+++ b/stmhal/uart.c
@@ -270,7 +270,7 @@ STATIC const mp_arg_t pyb_uart_init_args[] = {
     { MP_QSTR_stop,     MP_ARG_KW_ONLY | MP_ARG_INT,  {.u_int = 1} },
     { MP_QSTR_parity,   MP_ARG_KW_ONLY | MP_ARG_OBJ,  {.u_obj = mp_const_none} },
 };
-#define PYB_UART_INIT_NUM_ARGS ARRAY_SIZE(pyb_uart_init_args)
+#define PYB_UART_INIT_NUM_ARGS MP_ARRAY_SIZE(pyb_uart_init_args)
 
 STATIC mp_obj_t pyb_uart_init_helper(pyb_uart_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // parse args
@@ -396,7 +396,7 @@ STATIC const mp_arg_t pyb_uart_send_args[] = {
     { MP_QSTR_send,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_UART_SEND_NUM_ARGS ARRAY_SIZE(pyb_uart_send_args)
+#define PYB_UART_SEND_NUM_ARGS MP_ARRAY_SIZE(pyb_uart_send_args)
 
 STATIC mp_obj_t pyb_uart_send(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // TODO assumes transmission size is 8-bits wide
@@ -438,7 +438,7 @@ STATIC const mp_arg_t pyb_uart_recv_args[] = {
     { MP_QSTR_recv,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
 };
-#define PYB_UART_RECV_NUM_ARGS ARRAY_SIZE(pyb_uart_recv_args)
+#define PYB_UART_RECV_NUM_ARGS MP_ARRAY_SIZE(pyb_uart_recv_args)
 
 STATIC mp_obj_t pyb_uart_recv(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
     // TODO assumes transmission size is 8-bits wide
diff --git a/teensy/Makefile b/teensy/Makefile
index 00f3514724..8244d52d31 100644
--- a/teensy/Makefile
+++ b/teensy/Makefile
@@ -23,7 +23,7 @@ INC += -I$(PY_SRC)
 INC += -I$(BUILD)
 INC += -I$(CORE_PATH)
 
-CFLAGS = $(INC) -Wall -ansi -std=gnu99 $(CFLAGS_CORTEX_M4)
+CFLAGS = $(INC) -Wall -ansi -std=gnu99 -nostdlib $(CFLAGS_CORTEX_M4)
 LDFLAGS = -nostdlib -T mk20dx256.ld
 LIBS = -L $(COMPILER_PATH)/../lib/gcc/arm-none-eabi/4.7.2/thumb2 -lgcc
 
diff --git a/tests/bench/arrayop-1-list_inplace.py b/tests/bench/arrayop-1-list_inplace.py
new file mode 100644
index 0000000000..0ee1ef2eca
--- /dev/null
+++ b/tests/bench/arrayop-1-list_inplace.py
@@ -0,0 +1,12 @@
+# Array operation
+# Type: list, inplace operation using for. What's good about this
+# method is that it doesn't require any extra memory allocation.
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        arr = [0] * 1000
+        for i in range(len(arr)):
+            arr[i] += 1
+
+bench.run(test)
diff --git a/tests/bench/arrayop-2-list_map.py b/tests/bench/arrayop-2-list_map.py
new file mode 100644
index 0000000000..9d5095c53a
--- /dev/null
+++ b/tests/bench/arrayop-2-list_map.py
@@ -0,0 +1,12 @@
+# Array operation
+# Type: list, map() call. This method requires allocation of
+# the same amount of memory as original array (to hold result
+# array). On the other hand, input array stays intact.
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        arr = [0] * 1000
+        arr2 = list(map(lambda x: x + 1, arr))
+
+bench.run(test)
diff --git a/tests/bench/arrayop-3-bytearray_inplace.py b/tests/bench/arrayop-3-bytearray_inplace.py
new file mode 100644
index 0000000000..a6d6280705
--- /dev/null
+++ b/tests/bench/arrayop-3-bytearray_inplace.py
@@ -0,0 +1,12 @@
+# Array operation
+# Type: bytearray, inplace operation using for. What's good about this
+# method is that it doesn't require any extra memory allocation.
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        arr = bytearray(b"\0" * 1000)
+        for i in range(len(arr)):
+            arr[i] += 1
+
+bench.run(test)
diff --git a/tests/bench/arrayop-4-bytearray_map.py b/tests/bench/arrayop-4-bytearray_map.py
new file mode 100644
index 0000000000..1b92a40961
--- /dev/null
+++ b/tests/bench/arrayop-4-bytearray_map.py
@@ -0,0 +1,12 @@
+# Array operation
+# Type: list, map() call. This method requires allocation of
+# the same amount of memory as original array (to hold result
+# array). On the other hand, input array stays intact.
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        arr = bytearray(b"\0" * 1000)
+        arr2 = bytearray(map(lambda x: x + 1, arr))
+
+bench.run(test)
diff --git a/tests/bench/bytebuf-1-inplace.py b/tests/bench/bytebuf-1-inplace.py
new file mode 100644
index 0000000000..7e7d9391cc
--- /dev/null
+++ b/tests/bench/bytebuf-1-inplace.py
@@ -0,0 +1,11 @@
+# Doing some operation on bytearray
+# Inplace - the most memory efficient way
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        ba = bytearray(b"\0" * 1000)
+        for i in range(len(ba)):
+            ba[i] += 1
+
+bench.run(test)
diff --git a/tests/bench/bytebuf-2-join_map_bytes.py b/tests/bench/bytebuf-2-join_map_bytes.py
new file mode 100644
index 0000000000..daa622991f
--- /dev/null
+++ b/tests/bench/bytebuf-2-join_map_bytes.py
@@ -0,0 +1,12 @@
+# Doing some operation on bytearray
+# Pretty weird way - map bytearray thru function, but make sure that
+# function return bytes of size 1, then join them together. Surely,
+# this is slowest way to do it.
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        ba = bytearray(b"\0" * 1000)
+        ba2 = b''.join(map(lambda x:bytes([x + 1]), ba))
+
+bench.run(test)
diff --git a/tests/bench/bytebuf-3-bytarray_map.py b/tests/bench/bytebuf-3-bytarray_map.py
new file mode 100644
index 0000000000..078d08e99b
--- /dev/null
+++ b/tests/bench/bytebuf-3-bytarray_map.py
@@ -0,0 +1,10 @@
+# Doing some operation on bytearray
+# No joins, but still map().
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        ba = bytearray(b"\0" * 1000)
+        ba2 = bytearray(map(lambda x: x + 1, ba))
+
+bench.run(test)
diff --git a/tests/bench/from_iter-1-list_bound.py b/tests/bench/from_iter-1-list_bound.py
new file mode 100644
index 0000000000..d209daecc5
--- /dev/null
+++ b/tests/bench/from_iter-1-list_bound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = list(l)
+
+bench.run(test)
diff --git a/tests/bench/from_iter-2-list_unbound.py b/tests/bench/from_iter-2-list_unbound.py
new file mode 100644
index 0000000000..be019c52fe
--- /dev/null
+++ b/tests/bench/from_iter-2-list_unbound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = list(map(lambda x: x, l))
+
+bench.run(test)
diff --git a/tests/bench/from_iter-3-tuple_bound.py b/tests/bench/from_iter-3-tuple_bound.py
new file mode 100644
index 0000000000..7b7fa36c6e
--- /dev/null
+++ b/tests/bench/from_iter-3-tuple_bound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = tuple(l)
+
+bench.run(test)
diff --git a/tests/bench/from_iter-4-tuple_unbound.py b/tests/bench/from_iter-4-tuple_unbound.py
new file mode 100644
index 0000000000..7c7f134c85
--- /dev/null
+++ b/tests/bench/from_iter-4-tuple_unbound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = tuple(map(lambda x: x, l))
+
+bench.run(test)
diff --git a/tests/bench/from_iter-5-bytes_bound.py b/tests/bench/from_iter-5-bytes_bound.py
new file mode 100644
index 0000000000..b793a3207e
--- /dev/null
+++ b/tests/bench/from_iter-5-bytes_bound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = bytes(l)
+
+bench.run(test)
diff --git a/tests/bench/from_iter-6-bytes_unbound.py b/tests/bench/from_iter-6-bytes_unbound.py
new file mode 100644
index 0000000000..20aa556277
--- /dev/null
+++ b/tests/bench/from_iter-6-bytes_unbound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = bytes(map(lambda x: x, l))
+
+bench.run(test)
diff --git a/tests/bench/from_iter-7-bytearray_bound.py b/tests/bench/from_iter-7-bytearray_bound.py
new file mode 100644
index 0000000000..72001a05c7
--- /dev/null
+++ b/tests/bench/from_iter-7-bytearray_bound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = bytearray(l)
+
+bench.run(test)
diff --git a/tests/bench/from_iter-8-bytearray_unbound.py b/tests/bench/from_iter-8-bytearray_unbound.py
new file mode 100644
index 0000000000..e2263b8ef9
--- /dev/null
+++ b/tests/bench/from_iter-8-bytearray_unbound.py
@@ -0,0 +1,8 @@
+import bench
+
+def test(num):
+    for i in iter(range(num//10000)):
+        l = [0] * 1000
+        l2 = bytearray(map(lambda x: x, l))
+
+bench.run(test)
diff --git a/tests/bench/funcall-1-inline.py b/tests/bench/funcall-1-inline.py
new file mode 100644
index 0000000000..fbeb79630d
--- /dev/null
+++ b/tests/bench/funcall-1-inline.py
@@ -0,0 +1,9 @@
+# Function call overhead test
+# Establish a baseline for performing a trivial operation inline
+import bench
+
+def test(num):
+    for i in iter(range(num)):
+        a = i + 1
+
+bench.run(test)
diff --git a/tests/bench/funcall-2-funcall.py b/tests/bench/funcall-2-funcall.py
new file mode 100644
index 0000000000..d5c36c60aa
--- /dev/null
+++ b/tests/bench/funcall-2-funcall.py
@@ -0,0 +1,12 @@
+# Function call overhead test
+# Perform the same trivial operation as global function call
+import bench
+
+def f(x):
+    return x + 1
+
+def test(num):
+    for i in iter(range(num)):
+        a = f(i)
+
+bench.run(test)
diff --git a/tests/bench/funcall-3-funcall-local.py b/tests/bench/funcall-3-funcall-local.py
new file mode 100644
index 0000000000..1a6d728c63
--- /dev/null
+++ b/tests/bench/funcall-3-funcall-local.py
@@ -0,0 +1,16 @@
+# Function call overhead test
+# Perform the same trivial operation as calling function, cached in a
+# local variable. This is commonly known optimization for overly dynamic
+# languages (the idea is to cut on symbolic look up overhead, as local
+# variables are accessed by offset, not by name)
+import bench
+
+def f(x):
+    return x + 1
+
+def test(num):
+    f_ = f
+    for i in iter(range(num)):
+        a = f_(i)
+
+bench.run(test)
diff --git a/tests/float/math-fun-bool.py b/tests/float/math-fun-bool.py
index cf718d4b80..57232857ab 100644
--- a/tests/float/math-fun-bool.py
+++ b/tests/float/math-fun-bool.py
@@ -1,6 +1,11 @@
 # Test the bool functions from math
 
-from math import isfinite, isnan, isinf
+try:
+    from math import isfinite, isnan, isinf
+except ImportError:
+    print("SKIP")
+    import sys
+    sys.exit()
 
 test_values = [1, 0, -1, 1.0, 0.0, -1.0, float('NaN'), float('Inf'), 
                -float('NaN'), -float('Inf')]
diff --git a/tests/float/math-fun.py b/tests/float/math-fun.py
index 7a37c58454..fa111e33e3 100644
--- a/tests/float/math-fun.py
+++ b/tests/float/math-fun.py
@@ -1,6 +1,11 @@
 # Tests the functions imported from math
 
-from math import *
+try:
+    from math import *
+except ImportError:
+    print("SKIP")
+    import sys
+    sys.exit()
 
 test_values = [-100., -1.23456, -1, -0.5, 0.0, 0.5, 1.23456, 100.]
 p_test_values = [0.1, 0.5, 1.23456]
diff --git a/unix/Makefile b/unix/Makefile
index 485009135f..afe268ae45 100644
--- a/unix/Makefile
+++ b/unix/Makefile
@@ -7,6 +7,9 @@ PROG = micropython
 # qstr definitions (must come before including py.mk)
 QSTR_DEFS = qstrdefsport.h
 
+# OS name, for simple autoconfig
+UNAME_S := $(shell uname -s)
+
 # include py core make definitions
 include ../py/py.mk
 
@@ -15,14 +18,18 @@ INC += -I$(PY_SRC)
 INC += -I$(BUILD)
 
 # compiler settings
-CFLAGS = $(INC) -Wall -Werror -ansi -std=gnu99 -DUNIX $(CFLAGS_MOD) $(COPT)
+CWARN = -Wall -Werror -Wno-error=cpp
+CFLAGS = $(INC) $(CWARN) -ansi -std=gnu99 -DUNIX $(CFLAGS_MOD) $(COPT) $(CFLAGS_EXTRA)
 
-UNAME_S := $(shell uname -s)
- ifeq ($(UNAME_S),Darwin)
-    LDFLAGS = $(LDFLAGS_MOD) -lm -Wl,-map,$@.map,-order_file,$(BUILD)/order.def
- else
-    LDFLAGS = $(LDFLAGS_MOD) -lm -Wl,-Map=$@.map,--cref
- endif
+# Debugging/Optimization
+ifdef DEBUG
+CFLAGS += -g
+COPT = -O0
+else
+COPT = -Os #-DNDEBUG
+endif
+
+LDFLAGS = $(LDFLAGS_MOD) -lm -Wl,-Map=$@.map,--cref $(LDFLAGS_EXTRA)
 
 ifeq ($(MICROPY_FORCE_32BIT),1)
 CFLAGS += -m32
@@ -56,14 +63,6 @@ SRC_MOD += modffi.c
 endif
 
 
-# Debugging/Optimization
-ifdef DEBUG
-CFLAGS += -g
-COPT = -O0
-else
-COPT = -Os #-DNDEBUG
-endif
-
 # source files
 SRC_C = \
 	main.c \
@@ -75,6 +74,9 @@ SRC_C = \
 	$(SRC_MOD)
 
 ifeq ($(UNAME_S),Darwin)
+
+LDFLAGS+ = -Wl,-order_file,$(BUILD)/order.def
+
 # Must be the last file in list of sources
 SRC_C += seg_helpers.c
 
diff --git a/unix/gccollect.c b/unix/gccollect.c
index 4f3b786e72..f24cc52495 100644
--- a/unix/gccollect.c
+++ b/unix/gccollect.c
@@ -97,7 +97,7 @@ void gc_helper_get_regs(regs_t arr) {
 }
 #endif
 
-#ifdef __thumb2__
+#if defined(__thumb2__) || defined(__thumb__) || defined(__arm__)
 typedef machine_uint_t regs_t[10];
 
 void gc_helper_get_regs(regs_t arr) {
@@ -130,8 +130,11 @@ void gc_collect(void) {
 
     gc_collect_start();
     // this traces the .bss section
-#ifdef __CYGWIN__
+#if defined( __CYGWIN__ )
 #define BSS_START __bss_start__
+#elif defined( _MSC_VER ) || defined( __MINGW32__ )
+#define BSS_START *bss_start
+#define _end *bss_end
 #else
 #define BSS_START __bss_start
 #endif
@@ -141,7 +144,8 @@ void gc_collect(void) {
     regs_t regs;
     gc_helper_get_regs(regs);
     // GC stack (and regs because we captured them)
-    gc_collect_root((void**)&regs, ((machine_uint_t)stack_top - (machine_uint_t)&regs) / sizeof(machine_uint_t));
+    void **regs_ptr = (void**)(void*)&regs;
+    gc_collect_root(regs_ptr, ((machine_uint_t)stack_top - (machine_uint_t)&regs) / sizeof(machine_uint_t));
     gc_collect_end();
 
     //printf("-----\n");
diff --git a/unix/main.c b/unix/main.c
index 26736e4318..552df9b804 100644
--- a/unix/main.c
+++ b/unix/main.c
@@ -201,8 +201,8 @@ int usage(char **argv) {
     impl_opts_cnt++;
 #if MICROPY_ENABLE_GC
     printf(
-"  heapsize=<n> -- set the heap size for the GC\n"
-);
+"  heapsize=<n> -- set the heap size for the GC (default %ld)\n"
+, heap_size);
     impl_opts_cnt++;
 #endif
 
@@ -365,7 +365,8 @@ int main(int argc, char **argv) {
                 return usage(argv);
             }
         } else {
-            char *basedir = realpath(argv[a], NULL);
+            char *pathbuf = malloc(PATH_MAX);
+            char *basedir = realpath(argv[a], pathbuf);
             if (basedir == NULL) {
                 fprintf(stderr, "%s: can't open file '%s': [Errno %d] ", argv[0], argv[a], errno);
                 perror("");
@@ -377,7 +378,7 @@ int main(int argc, char **argv) {
             // Set base dir of the script as first entry in sys.path
             char *p = strrchr(basedir, '/');
             path_items[0] = MP_OBJ_NEW_QSTR(qstr_from_strn(basedir, p - basedir));
-            free(basedir);
+            free(pathbuf);
 
             for (int i = a; i < argc; i++) {
                 mp_obj_list_append(mp_sys_argv, MP_OBJ_NEW_QSTR(qstr_from_str(argv[i])));
diff --git a/unix/modffi.c b/unix/modffi.c
index bfc840ceff..f1b219987b 100644
--- a/unix/modffi.c
+++ b/unix/modffi.c
@@ -421,8 +421,8 @@ STATIC const mp_obj_dict_t mp_module_ffi_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_ffi_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_ffi_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_ffi_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_ffi_globals_table),
         .table = (mp_map_elem_t*)mp_module_ffi_globals_table,
     },
 };
diff --git a/unix/modos.c b/unix/modos.c
index 657958d04c..2e02ef0aa7 100644
--- a/unix/modos.c
+++ b/unix/modos.c
@@ -75,8 +75,8 @@ STATIC const mp_obj_dict_t mp_module_os_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_os_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_os_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_os_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_os_globals_table),
         .table = (mp_map_elem_t*)mp_module_os_globals_table,
     },
 };
diff --git a/unix/modsocket.c b/unix/modsocket.c
index b1a34a39b8..5b3fb01877 100644
--- a/unix/modsocket.c
+++ b/unix/modsocket.c
@@ -356,6 +356,8 @@ STATIC mp_obj_t mod_socket_getaddrinfo(uint n_args, const mp_obj_t *args) {
 
     const char *host = mp_obj_str_get_str(args[0]);
     const char *serv = NULL;
+    struct addrinfo hints;
+    memset(&hints, 0, sizeof(hints));
     // getaddrinfo accepts port in string notation, so however
     // it may seem stupid, we need to convert int to str
     if (MP_OBJ_IS_SMALL_INT(args[1])) {
@@ -363,23 +365,35 @@ STATIC mp_obj_t mod_socket_getaddrinfo(uint n_args, const mp_obj_t *args) {
         char buf[6];
         sprintf(buf, "%d", port);
         serv = buf;
+        hints.ai_flags = AI_NUMERICSERV;
+#ifdef __UCLIBC_MAJOR__
+#if __UCLIBC_MAJOR__ == 0 && (__UCLIBC_MINOR__ < 9 || (__UCLIBC_MINOR__ == 9 && __UCLIBC_SUBLEVEL__ <= 32))
+#warning Working around uClibc bug with numeric service name
+        // Older versions og uClibc have bugs when numeric ports in service
+        // arg require also hints.ai_socktype (or hints.ai_protocol) != 0
+        // This actually was fixed in 0.9.32.1, but uClibc doesn't allow to
+        // test for that.
+        // http://git.uclibc.org/uClibc/commit/libc/inet/getaddrinfo.c?id=bc3be18145e4d5
+        // Note that this is crude workaround, precluding UDP socket addresses
+        // to be returned. TODO: set only if not set by Python args.
+        hints.ai_socktype = SOCK_STREAM;
+#endif
+#endif
     } else {
         serv = mp_obj_str_get_str(args[1]);
     }
 
-    struct addrinfo hints;
-    struct addrinfo *addr;
-    memset(&hints, 0, sizeof(hints));
-    int res = getaddrinfo(host, serv, NULL/*&hints*/, &addr);
+    struct addrinfo *addr_list;
+    int res = getaddrinfo(host, serv, &hints, &addr_list);
 
     if (res != 0) {
         // CPython: socket.gaierror
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OSError, "[addrinfo error %d]", res));
     }
-    assert(addr);
+    assert(addr_list);
 
     mp_obj_t list = mp_obj_new_list(0, NULL);
-    for (; addr; addr = addr->ai_next) {
+    for (struct addrinfo *addr = addr_list; addr; addr = addr->ai_next) {
         mp_obj_tuple_t *t = mp_obj_new_tuple(5, NULL);
         t->items[0] = MP_OBJ_NEW_SMALL_INT((machine_int_t)addr->ai_family);
         t->items[1] = MP_OBJ_NEW_SMALL_INT((machine_int_t)addr->ai_socktype);
@@ -394,6 +408,7 @@ STATIC mp_obj_t mod_socket_getaddrinfo(uint n_args, const mp_obj_t *args) {
         t->items[4] = mp_obj_new_bytearray(addr->ai_addrlen, addr->ai_addr);
         mp_obj_list_append(list, t);
     }
+    freeaddrinfo(addr_list);
     return list;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_socket_getaddrinfo_obj, 2, 6, mod_socket_getaddrinfo);
@@ -436,8 +451,8 @@ STATIC const mp_obj_dict_t mp_module_socket_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_socket_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_socket_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_socket_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_socket_globals_table),
         .table = (mp_map_elem_t*)mp_module_socket_globals_table,
     },
 };
diff --git a/unix/modtime.c b/unix/modtime.c
index 3cc09e3cd8..006fd0ebd7 100644
--- a/unix/modtime.c
+++ b/unix/modtime.c
@@ -113,8 +113,8 @@ STATIC const mp_obj_dict_t mp_module_time_globals = {
     .map = {
         .all_keys_are_qstrs = 1,
         .table_is_fixed_array = 1,
-        .used = ARRAY_SIZE(mp_module_time_globals_table),
-        .alloc = ARRAY_SIZE(mp_module_time_globals_table),
+        .used = MP_ARRAY_SIZE(mp_module_time_globals_table),
+        .alloc = MP_ARRAY_SIZE(mp_module_time_globals_table),
         .table = (mp_map_elem_t*)mp_module_time_globals_table,
     },
 };
diff --git a/unix/mpconfigport.h b/unix/mpconfigport.h
index 3426ae44fe..1559bdb359 100644
--- a/unix/mpconfigport.h
+++ b/unix/mpconfigport.h
@@ -53,7 +53,9 @@
 #define MICROPY_ERROR_REPORTING     (MICROPY_ERROR_REPORTING_DETAILED)
 // Define to 1 to use untested inefficient GC helper implementation
 // (if more efficient arch-specific one is not available).
+#ifndef MICROPY_GCREGS_SETJMP
 #define MICROPY_GCREGS_SETJMP       (0)
+#endif
 
 extern const struct _mp_obj_module_t mp_module_os;
 extern const struct _mp_obj_module_t mp_module_time;
diff --git a/windows/Makefile b/windows/Makefile
index a188979bd5..e3085ff23b 100644
--- a/windows/Makefile
+++ b/windows/Makefile
@@ -35,9 +35,11 @@ SRC_C = \
 	unix/file.c \
 	unix/input.c \
 	unix/modtime.c \
+	unix/gccollect.c \
 	realpath.c \
 	init.c \
 	sleep.c \
+	bss.c \
 
 OBJ = $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 
diff --git a/windows/bss.c b/windows/bss.c
new file mode 100644
index 0000000000..b860c4ee85
--- /dev/null
+++ b/windows/bss.c
@@ -0,0 +1,74 @@
+/*
+* This file is part of the Micro Python project, http://micropython.org/
+*
+* The MIT License (MIT)
+*
+* Copyright (c) 2013, 2014 Damien P. George
+*
+* Permission is hereby granted, free of charge, to any person obtaining a copy
+* of this software and associated documentation files (the "Software"), to deal
+* in the Software without restriction, including without limitation the rights
+* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+* copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included in
+* all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+* THE SOFTWARE.
+*/
+
+#include "mpconfig.h"
+#include "misc.h"
+#include "nlr.h"
+#include "qstr.h"
+#include "obj.h"
+#include <windows.h>
+
+IMAGE_NT_HEADERS *header_from_memory(const char *module) {
+    BYTE *base_addr = (BYTE*)GetModuleHandleA(module);
+    IMAGE_DOS_HEADER *dos_header = (IMAGE_DOS_HEADER*)base_addr;
+    return (IMAGE_NT_HEADERS*)(base_addr + dos_header->e_lfanew);
+}
+
+IMAGE_SECTION_HEADER *find_section(IMAGE_NT_HEADERS *nt_header, const char *name) {
+    int i;
+    IMAGE_SECTION_HEADER *section = IMAGE_FIRST_SECTION(nt_header);
+    for (i = 0; i < nt_header->FileHeader.NumberOfSections; ++i) {
+        if (strcmp((const char *)section->Name, name) == 0) {
+            return section;
+        }
+        ++section;
+    }
+    return NULL;
+}
+
+void section_boundaries(IMAGE_NT_HEADERS *nt_header, IMAGE_SECTION_HEADER *section, char **start, char **end) {
+    if (section == NULL) {
+        nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, "Could not lookup section boundaries"));
+    }
+    *start = (char*)(nt_header->OptionalHeader.ImageBase + section->VirtualAddress);
+    *end = *start + section->Misc.VirtualSize;    
+}
+
+void section_boundaries_from_module(const char *module, const char *section, char **start, char **end) {
+    IMAGE_NT_HEADERS *nt_header = header_from_memory(module);
+    IMAGE_SECTION_HEADER *dsection = find_section(nt_header, section);
+    section_boundaries(nt_header, dsection, start, end);   
+}
+
+char *bss_start = 0;
+char *bss_end = 0;
+
+//MSVC has no __bss_start and _end but we can get accurate section info from the PE header.
+//The standard .bss section is appended to the standard .data section however so it cannot
+//be looked up by name. To deal with that we put all uPy static variables in a named section.
+void getbss() {
+    section_boundaries_from_module(NULL, MICROPY_PORT_BSSSECTION, &bss_start, &bss_end);
+}
diff --git a/windows/init.c b/windows/init.c
index a370c464e8..57f349ef89 100644
--- a/windows/init.c
+++ b/windows/init.c
@@ -28,9 +28,12 @@
 #include <stdio.h>
 #include <windows.h>
 
+extern void getbss();
+
 HANDLE hSleepEvent = NULL;
 
 void init() {
+    getbss();
     hSleepEvent = CreateEvent(NULL, TRUE, FALSE, FALSE);
 #ifdef __MINGW32__
     putenv("PRINTF_EXPONENT_DIGITS=2");
diff --git a/windows/mpconfigport.h b/windows/mpconfigport.h
index b9a50b0841..c930fe95e8 100644
--- a/windows/mpconfigport.h
+++ b/windows/mpconfigport.h
@@ -43,6 +43,12 @@
 #define MICROPY_PY_CMATH            (1)
 #define MICROPY_PY_SYS_STDFILES     (1)
 #define MICROPY_PY_SYS_EXIT         (1)
+#define MICROPY_ENABLE_GC           (1)
+#define MICROPY_ENABLE_FINALISER    (1)
+#define MICROPY_PY_GC_COLLECT_RETVAL (1)
+#ifdef _MSC_VER
+#define MICROPY_GCREGS_SETJMP       (1)
+#endif
 #define MICROPY_FLOAT_IMPL          (MICROPY_FLOAT_IMPL_DOUBLE)
 #define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
 #define MICROPY_PORT_INIT_FUNC      init()
@@ -113,6 +119,14 @@ void msec_sleep(double msec);
 #define S_ISDIR(m)                  (((m) & S_IFMT) == S_IFDIR)
 
 
+// Put static/global variables in sections with a known name we can lookup for the GC
+// For this to work this header must be included by all sources, which is the case normally
+#define MICROPY_PORT_DATASECTION "upydata"
+#define MICROPY_PORT_BSSSECTION "upybss"
+#pragma data_seg(MICROPY_PORT_DATASECTION)
+#pragma bss_seg(MICROPY_PORT_BSSSECTION)
+
+
 // System headers (needed e.g. for nlr.h)
 
 #include <stddef.h> //for NULL
@@ -122,3 +136,8 @@ void msec_sleep(double msec);
 
 int snprintf(char *dest, size_t count, const char *format, ...);
 #endif
+
+// MingW specifics
+#ifdef __MINGW32__
+#define MICROPY_PORT_BSSSECTION ".bss"
+#endif
diff --git a/windows/msvc/common.props b/windows/msvc/common.props
index 300de46a53..b6f22c6151 100644
--- a/windows/msvc/common.props
+++ b/windows/msvc/common.props
@@ -16,7 +16,8 @@
     </ClCompile>
     <Link>
       <GenerateDebugInformation>true</GenerateDebugInformation>
+      <GenerateMapFile>true</GenerateMapFile>
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup />
-</Project>
\ No newline at end of file
+</Project>
diff --git a/windows/msvc/sources.props b/windows/msvc/sources.props
index 8af03e7563..6fd3306b92 100644
--- a/windows/msvc/sources.props
+++ b/windows/msvc/sources.props
@@ -5,7 +5,7 @@
   </PropertyGroup>
   <ItemGroup>
     <ClCompile Include="$(PyBaseDir)py\*.c" />
-    <ClCompile Include="$(PyBaseDir)unix\*.c" Exclude="$(PyBaseDir)unix\modffi.c;$(PyBaseDir)unix\modsocket.c" />
+    <ClCompile Include="$(PyBaseDir)unix\*.c" Exclude="$(PyBaseDir)unix\modffi.c;$(PyBaseDir)unix\modsocket.c;$(PyBaseDir)unix\seg_helpers.c" />
     <ClCompile Include="$(PyBaseDir)windows\*.c" />
     <ClCompile Include="$(PyBaseDir)windows\msvc\*.c" />
   </ItemGroup>