diff --git a/boards.txt b/boards.txt
index e61d8f177..e98359138 100644
--- a/boards.txt
+++ b/boards.txt
@@ -421,6 +421,9 @@ espresso_lite_v1.menu.ResetMethod.nodemcu.upload.resetmethod=nodemcu
 espresso_lite_v1.menu.ResetMethod.ck=ck
 espresso_lite_v1.menu.ResetMethod.ck.upload.resetmethod=ck
 
+espresso_lite_v1.build.debug_port=
+espresso_lite_v1.build.debug_level=
+
 ##############################################################
 espresso_lite_v2.name=ESPresso Lite 2.0
 espresso_lite_v2.upload.tool=esptool
@@ -491,6 +494,9 @@ espresso_lite_v2.menu.ResetMethod.ck.upload.resetmethod=ck
 espresso_lite_v2.menu.ResetMethod.nodemcu=nodemcu
 espresso_lite_v2.menu.ResetMethod.nodemcu.upload.resetmethod=nodemcu
 
+espresso_lite_v2.build.debug_port=
+espresso_lite_v2.build.debug_level=
+
 ##############################################################
 nodemcu.name=NodeMCU 0.9 (ESP-12 Module)
 
diff --git a/cores/esp8266/umm_malloc/umm_malloc.h b/cores/esp8266/umm_malloc/umm_malloc.h
index 7f1c05849..0019b0ec5 100644
--- a/cores/esp8266/umm_malloc/umm_malloc.h
+++ b/cores/esp8266/umm_malloc/umm_malloc.h
@@ -12,6 +12,10 @@
 
 #include "umm_malloc_cfg.h"   /* user-dependent */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct UMM_HEAP_INFO_t {
   unsigned short int totalEntries;
   unsigned short int usedEntries;
@@ -38,6 +42,9 @@ void umm_free( void *ptr );
 
 size_t umm_free_heap_size( void );
 
+#ifdef __cplusplus
+}
+#endif
 
 /* ------------------------------------------------------------------------ */
 
diff --git a/cores/esp8266/umm_malloc/umm_malloc_cfg.h b/cores/esp8266/umm_malloc/umm_malloc_cfg.h
index 544545a47..87a5a167c 100644
--- a/cores/esp8266/umm_malloc/umm_malloc_cfg.h
+++ b/cores/esp8266/umm_malloc/umm_malloc_cfg.h
@@ -7,7 +7,7 @@
 
 #include <debug.h>
 #ifdef __cplusplus
-#extern "C" {
+extern "C" {
 #endif
 #include "c_types.h"
 #ifdef __cplusplus
diff --git a/doc/boards.md b/doc/boards.md
index 4f36c1f91..cdfd681f1 100644
--- a/doc/boards.md
+++ b/doc/boards.md
@@ -37,7 +37,7 @@ title: Supported Hardware
 
 ## ESPresso Lite 1.0
 
-ESPresso Lite 1.0 (beta version) is an Arduino-compatible Wi-Fi development board powered by Espressif System's own ESP8266 WROOM-02 module. It has breadboard-friendly breakout pins with in-built LED, two reset/flash buttons and a user programmable button . The operating voltage is 3.3VDC, regulated with 800mA maximum current. Special distinctive features include on-board I2C pads that allow direct connection to OLED LCD and sensor boards. (Only 500? units were produced for beta testing before it was retired to make way for the improved V2.0 - i presumed we wont be using this design?)
+ESPresso Lite 1.0 (beta version) is an Arduino-compatible Wi-Fi development board powered by Espressif System's own ESP8266 WROOM-02 module. It has breadboard-friendly breakout pins with in-built LED, two reset/flash buttons and a user programmable button . The operating voltage is 3.3VDC, regulated with 800mA maximum current. Special distinctive features include on-board I2C pads that allow direct connection to OLED LCD and sensor boards.
 
 ## ESPresso Lite 2.0
 
diff --git a/tests/.gitignore b/tests/.gitignore
new file mode 100644
index 000000000..7bce08d60
--- /dev/null
+++ b/tests/.gitignore
@@ -0,0 +1,3 @@
+hardware
+tmp
+.env
diff --git a/tests/test_umm_malloc/test_umm_malloc.ino b/tests/test_umm_malloc/test_umm_malloc.ino
new file mode 100644
index 000000000..16348bc70
--- /dev/null
+++ b/tests/test_umm_malloc/test_umm_malloc.ino
@@ -0,0 +1,13 @@
+// test that we can include umm_malloc.h from sketch (#1652)
+#include <umm_malloc/umm_malloc.h>
+
+
+void setup() {
+    Serial.begin(115200);
+    delay(1000);
+    umm_info(NULL, 1);
+}
+
+void loop() {
+
+}
diff --git a/tools/sdk/ld/eagle.app.v6.common.ld b/tools/sdk/ld/eagle.app.v6.common.ld
index c15376233..c731ece35 100644
--- a/tools/sdk/ld/eagle.app.v6.common.ld
+++ b/tools/sdk/ld/eagle.app.v6.common.ld
@@ -154,6 +154,8 @@ SECTIONS
            EXCLUDE_FILE (umm_malloc.c.o) .text*)
     *.cpp.o(.literal*, .text*)
     *libm.a:(.literal .text .literal.* .text.*)
+    *libgcc.a:_umoddi3.o(.literal .text)
+    *libgcc.a:_udivdi3.o(.literal .text)
     *libsmartconfig.a:(.literal .text .literal.* .text.*)
     *(.irom0.literal .irom.literal .irom.text.literal .irom0.text .irom.text .irom.text.*)
     _irom0_text_end = ABSOLUTE(.);