diff --git a/targets/mbedos5/mbed-os.lib b/targets/mbedos5/mbed-os.lib
index efedfa803..32c1c7f8a 100644
--- a/targets/mbedos5/mbed-os.lib
+++ b/targets/mbedos5/mbed-os.lib
@@ -1 +1 @@
-https://github.com/ARMmbed/mbed-os/#51d55508e8400b60af467005646c4e2164738d48
+https://github.com/ARMmbed/mbed-os/#e4b81f67f939a0c0b11c147ce74aa367271e1279
diff --git a/targets/mbedos5/tools/generate_pins.py b/targets/mbedos5/tools/generate_pins.py
index 10a688935..a35bca4a5 100644
--- a/targets/mbedos5/tools/generate_pins.py
+++ b/targets/mbedos5/tools/generate_pins.py
@@ -157,7 +157,7 @@ unsigned int jsmbed_js_magic_string_lengths[] = {
 
     magic_values = ',\n    '.join(pins)
     magic_source = '''
-unsigned int jsmbed_js_magic_string_values[] = {
+int jsmbed_js_magic_string_values[] = {
     %s
 };
     ''' % magic_values
diff --git a/targets/mbedos5/tools/requirements.txt b/targets/mbedos5/tools/requirements.txt
index 54b167dc1..df41b1eb3 100644
--- a/targets/mbedos5/tools/requirements.txt
+++ b/targets/mbedos5/tools/requirements.txt
@@ -1,3 +1,2 @@
-pycparser
-simpleeval
 pycparserext
+simpleeval