Merge branch 'feature/toolchain_update' into 'master'

update toolchain version, rebuild newlib

- This MR updates the toolchain version used in the ESP-IDF
- Compiler version check and warning is added to project.mk
- Newlib is rebuilt to include wcsftime function
- libstdc++ build uses correct newlib headers (so we won't get undefined reference to `__impure_ptr` anymore)

See merge request !387

components/cxx/test/test_cxx.cpp

@@ -1,6 +1,7 @@
 #include <functional>
 #include <vector>
 #include <algorithm>
+#include <iostream>
 #include "unity.h"
 #include "esp_log.h"
 #include "freertos/FreeRTOS.h"
@@ -201,3 +202,9 @@ TEST_CASE("before scheduler has started, static initializers work correctly", "[
     TEST_ASSERT_EQUAL(1, g_static_init_test3.index);
     TEST_ASSERT_EQUAL(2, StaticInitTestBeforeScheduler::order);
 }
+
+
+TEST_CASE("can use iostreams", "[cxx]")
+{
+    std::cout << "hello world";
+}

docs/linux-setup.rst

@@ -24,17 +24,17 @@ ESP32 toolchain for Linux is available for download from Espressif website:
 
 - for 64-bit Linux::
 
-    https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-1.22.0-59.tar.gz
+    https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-1.22.0-61-gab8375a-5.2.0.tar.gz
 
 - for 32-bit Linux::
 
-    https://dl.espressif.com/dl/xtensa-esp32-elf-linux32-1.22.0-59.tar.gz
+    https://dl.espressif.com/dl/xtensa-esp32-elf-linux32-1.22.0-61-gab8375a-5.2.0.tar.gz
 
 Download this file, then extract it to the location you prefer, for example::
 
     mkdir -p ~/esp
     cd ~/esp
-    tar -xzf ~/Downloads/xtensa-esp32-elf-linux64-1.22.0-59.tar.gz
+    tar -xzf ~/Downloads/xtensa-esp32-elf-linux64-1.22.0-61-gab8375a-5.2.0.tar.gz
 
 The toolchain will be extracted into ``~/esp/xtensa-esp32-elf/`` directory.
 
@@ -67,6 +67,8 @@ If you can't think of a reason why you need to build it yourself, then probably
 
 - if you want to customize toolchain build configuration
 
+- if you want to use a different GCC version (such as 4.8.5)
+
 - if you want to hack gcc or newlib or libstdc++
 
 - if you are curious and/or have time to spare
@@ -79,7 +81,7 @@ In any case, here are the steps to compile the toolchain yourself.
 
   - Ubuntu::
 
-        sudo apt-get install gawk gperf grep gettext ncurses python python-dev automake bison flex texinfo help2man libtool
+        sudo apt-get install gawk gperf grep gettext libncurses-dev python python-dev automake bison flex texinfo help2man libtool
 
   - Debian::
 

docs/macos-setup.rst

@@ -23,13 +23,13 @@ Step 1: Download binary toolchain for the ESP32
 
 ESP32 toolchain for macOS is available for download from Espressif website:
 
-https://dl.espressif.com/dl/xtensa-esp32-elf-osx-1.22.0-59.tar.gz
+https://dl.espressif.com/dl/xtensa-esp32-elf-osx-1.22.0-61-gab8375a-5.2.0.tar.gz
 
 Download this file, then extract it to the location you prefer, for example::
 
     mkdir -p ~/esp
     cd ~/esp
-    tar -xzf ~/Downloads/xtensa-esp32-elf-osx-1.22.0-59.tar.gz
+    tar -xzf ~/Downloads/xtensa-esp32-elf-osx-1.22.0-61-gab8375a-5.2.0.tar.gz
 
 The toolchain will be extracted into ``~/esp/xtensa-esp32-elf/`` directory.
 
@@ -52,6 +52,8 @@ If you can't think of a reason why you need to build it yourself, then probably
 
 - if you want to customize toolchain build configuration
 
+- if you want to use a different GCC version (such as 4.8.5)
+
 - if you want to hack gcc or newlib or libstdc++
 
 - if you are curious and/or have time to spare
@@ -160,4 +162,3 @@ Further reading
 ===============
 
 If you'd like to use the Eclipse IDE instead of running ``make``, check out the Eclipse setup guide in this directory.
-

docs/windows-setup.rst

@@ -9,7 +9,7 @@ Windows doesn't have a built-in "make" environment, so as well as installing the
 
 The quick setup is to download the Windows all-in-one toolchain & MSYS zip file from dl.espressif.com:
 
-https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_toolchain-20160816.zip
+https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_toolchain-20170111.zip
 
 Unzip the zip file to C:\ and it will create an "msys32" directory with a pre-prepared environment.
 
@@ -38,7 +38,7 @@ Another Alternative Step 1: Just download a toolchain
 
 If you already have an MSYS2 install or want to do things differently, you can download just the toolchain here:
 
-https://dl.espressif.com/dl/xtensa-esp32-elf-win32-1.22.0-59.zip
+https://dl.espressif.com/dl/xtensa-esp32-elf-win32-1.22.0-61-gab8375a-5.2.0.zip
 
 If you followed one of the above options for Step 1, you won't need this download.
 

make/project.mk

@@ -421,3 +421,30 @@ endef
 # filter/subst in expression ensures all submodule paths begin with $(IDF_PATH), and then strips that prefix
 # so the argument is suitable for use with 'git submodule' commands
 $(foreach submodule,$(subst $(IDF_PATH)/,,$(filter $(IDF_PATH)/%,$(COMPONENT_SUBMODULES))),$(eval $(call GenerateSubmoduleCheckTarget,$(submodule))))
+
+
+# Check toolchain version using the output of xtensa-esp32-elf-gcc --version command.
+# The output normally looks as follows
+#     xtensa-esp32-elf-gcc (crosstool-NG crosstool-ng-1.22.0-59-ga194053) 4.8.5
+# The part in brackets is extracted into TOOLCHAIN_COMMIT_DESC variable,
+# the part after the brackets is extracted into TOOLCHAIN_GCC_VER.
+ifndef MAKE_RESTARTS
+TOOLCHAIN_COMMIT_DESC := $(shell $(CC) --version | sed -E -n 's|xtensa-esp32-elf-gcc\ \(([^)]*).*|\1|gp')
+TOOLCHAIN_GCC_VER := $(shell $(CC) --version | sed -E -n 's|xtensa-esp32-elf-gcc\ \(.*\)\ (.*)|\1|gp')
+
+# Officially supported version(s)
+SUPPORTED_TOOLCHAIN_COMMIT_DESC := crosstool-NG crosstool-ng-1.22.0-61-gab8375a
+SUPPORTED_TOOLCHAIN_GCC_VERSIONS := 5.2.0
+
+ifneq ($(TOOLCHAIN_COMMIT_DESC), $(SUPPORTED_TOOLCHAIN_COMMIT_DESC))
+$(info WARNING: Toolchain version is not supported: $(TOOLCHAIN_COMMIT_DESC))
+$(info Expected to see version: $(SUPPORTED_TOOLCHAIN_COMMIT_DESC))
+$(info Please check ESP-IDF setup instructions and update the toolchain, or proceed at your own risk.)
+endif
+ifeq (,$(findstring $(TOOLCHAIN_GCC_VER), $(SUPPORTED_TOOLCHAIN_GCC_VERSIONS)))
+$(warning WARNING: Compiler version is not supported: $(TOOLCHAIN_GCC_VER))
+$(info Expected to see version(s): $(SUPPORTED_TOOLCHAIN_GCC_VERSIONS))
+$(info Please check ESP-IDF setup instructions and update the toolchain, or proceed at your own risk.)
+endif
+endif #MAKE_RESTARTS 
+