Eclipse IDE on Windows

Configuring Eclipse on Windows requires some different steps. The full configuration steps for Windows are shown below.

(For OS X and Linux instructions, see the Eclipse IDE page.)

Installing Eclipse IDE

Follow the steps under Installing Eclipse IDE for all platforms.

Setting up Eclipse on Windows

Once your new Eclipse installation launches, follow these steps:

Import New Project

  • Eclipse makes use of the Makefile support in ESP8266_RTOS_SDK. This means you need to start by creating an ESP8266_RTOS_SDK project. You can use the idf-template project from github, or open one of the examples in the ESP8266_RTOS_SDK examples subdirectory.
  • Once Eclipse is running, choose File -> Import…
  • In the dialog that pops up, choose “C/C++” -> “Existing Code as Makefile Project” and click Next.
  • On the next page, enter “Existing Code Location” to be the directory of your ESP8266_RTOS_SDK project. Don’t specify the path to the ESP8266_RTOS_SDK directory itself (that comes later). The directory you specify should contain a file named “Makefile” (the project Makefile).
  • On the same page, under “Toolchain for Indexer Settings” uncheck “Show only available toolchains that support this platform”.
  • On the extended list that appears, choose “Cygwin GCC”. Then click Finish.

Note: you may see warnings in the UI that Cygwin GCC Toolchain could not be found. This is OK, we’re going to reconfigure Eclipse to find our toolchain.

Project Properties

  • The new project will appear under Project Explorer. Right-click the project and choose Properties from the context menu.

  • Click on the “C/C++ Build” properties page (top-level):

    • Uncheck “Use default build command” and enter this for the custom build command: python ${IDF_PATH}/tools/windows/eclipse_make.py
  • Click on the “Environment” properties page under “C/C++ Build”:

    • Click “Add…” and enter name BATCH_BUILD and value 1.
    • Click “Add…” again, and enter name IDF_PATH. The value should be the full path where ESP8266_RTOS_SDK is installed. The IDF_PATH directory should be specified using forwards slashes not backslashes, ie C:/Users/user-name/Development/ESP8266_RTOS_SDK.
    • Edit the PATH environment variable. Delete the existing value and replace it with C:\msys32\usr\bin;C:\msys32\mingw32\bin;C:\msys32\opt\xtensa-lx106-elf\bin (If you installed msys32 to a different directory then you’ll need to change these paths to match).
  • Click on “C/C++ General” -> “Preprocessor Include Paths, Macros, etc.” property page:

    • Click the “Providers” tab

      • In the list of providers, click “CDT Cross GCC Built-in Compiler Settings”. Change “Command to get compiler specs” to xtensa-lx106-elf-gcc ${FLAGS} -E -P -v -dD "${INPUTS}".
      • In the list of providers, click “CDT GCC Build Output Parser” and change the “Compiler command pattern” to xtensa-lx106-elf-(gcc|g\+\+|c\+\+|cc|cpp|clang)

Navigate to “C/C++ General” -> “Indexer” property page:

  • Check “Enable project specific settings” to enable the rest of the settings on this page.
  • Uncheck “Allow heuristic resolution of includes”. When this option is enabled Eclipse sometimes fails to find correct header directories.

Navigate to “C/C++ Build” -> “Behavior” property page:

  • Check “Enable parallel build” to enable multiple build jobs in parallel.
  • Setting the number of jobs slightly higher than the “optimal” may give the absolute fastest builds under Windows, depending on the specific hardware being used.

Building in Eclipse

Continue from Building in Eclipse for all platforms.

Technical Details

Of interest to Windows gurus or very curious parties, only.

Explanations of the technical reasons for some of these steps. You don’t need to know this to use ESP8266_RTOS_SDK with Eclipse on Windows, but it may be helpful background knowledge if you plan to do dig into the Eclipse support:

  • The xtensa-lx106-elf-gcc cross-compiler is not a Cygwin toolchain, even though we tell Eclipse that it is one. This is because msys2 uses Cygwin and supports Unix-style paths (of the type /c/blah instead of c:/blah or c:\\blah). In particular, xtensa-lx106-elf-gcc reports to the Eclipse “built-in compiler settings” function that its built-in include directories are all under /usr/, which is a Unix/Cygwin-style path that Eclipse otherwise can’t resolve. By telling Eclipse the compiler is Cygwin, it resolves these paths internally using the cygpath utility.
  • The same problem occurs when parsing make output from ESP8266_RTOS_SDK. Eclipse parses this output to find header directories, but it can’t resolve include directories of the form /c/blah without using cygpath. There is a heuristic that Eclipse Build Output Parser uses to determine whether it should call cygpath, but for currently unknown reasons the ESP8266_RTOS_SDK configuration doesn’t trigger it. For this reason, the eclipse_make.py wrapper script is used to call make and then use cygpath to process the output for Eclipse.