Q: On my Mac, after following the instructions in "Upgrading GCC on the Mac," I get an error that says:

    unrecognized command line option "-std=c++11"

A: This means that Eclipse is not invoking the correct version of GCC.

This may be caused by one of two conditions:
1) The hpc-gcc installation is not in the expected location, or
2) The environment variables are incorrect in the Working project settings.

To check the location of the hpc-gcc installation, launch Terminal and type this command:

        ls -l ~/hpc-gcc/

Your result should look something like this:

        $ ls -l ~/hpc-gcc/
        total 0
        drwxr-xr-x  19 billw  staff   646 Jun  7 13:49 bin/
        drwxr-xr-x   7 billw  staff   238 Apr 14 15:15 include/
        drwxr-xr-x  53 billw  staff  1802 Jun  7 13:50 lib/
        drwxr-xr-x   3 billw  staff   102 Mar 17 10:20 libexec/
        drwxr-xr-x   2 billw  staff    68 Jun  7 13:59 share/

If this is not the result you see, follow the instructions again in the first part of the "Upgrading GCC on the Mac" movie to unarchive the compiler and move it into place in your home directory.

 To check that your Working project environment settings are correct follow these steps:

    1. Open Eclipse
    2. In the Project Explorer, select your Working project
    3. Press CMD-I (or Control-click on the Working project) and select "Properties" from the context menu
    4. Expand the C/C++ Build section and select Environment
    5. Check that the Configuration says "Debug [ Active ]"

The Environment variables list should include these entries (they should be highlighted):

        CPATH           ${HOME}/hpc-gcc/include
        LIBRARY_PATH    ${HOME}/hpc-gcc/lib
        PATH            ${HOME}/hpc-gcc/bin:/usr/bin:/bin:/usr/sbin:/sbin

If any of these variables look wrong, you may correct them by selecting an individual variable and pressing the Edit button.

After correcting either of these problems, you should clean the project before trying again. Select Clean from the Project menu, press "Clean all projects," and press the OK button

Q: I am using OS X Snow Leopard (10.6.x) on a Mac. I downloaded the Snow Leopard version of HPC GCC and installed it according to the instructions, but I get this error:

    unrecognized command line option ‘-std=c++11’

A: As of the date of this writing, the Snow Leopard version of hpc-gcc is based on an older version of GCC that does yet support the -std=c++11 switch. Instead, it uses an older version of the -std switch.

In order to use the Snow Leopard version of HPC GCC you will need to change two settings after your installation. Please follow these instructions.

    1. Open Eclipse
    2. In the Project Explorer, select your Working project
    3. Press CMD-I (or Control-click on the Working project) and select "Properties" from the context menu
    4. Expand the C/C++ Build section and select Settings
    5. Under GCC C++ Compiler, select Miscellaneous and change -std=c++11 to -std=c++0x
    5. Under GCC C Compiler, select Miscellaneous and change -std=gnu11 to -std=gnu99

After making these changes, you should be able to follow along with the exercises.

Q: Why is my Working project missing folders for Includes and Debug, and why can't I build my project?

A: This happens if you create a Makefile project instead of a C++ project. You need to delete your Working project and create it again. When you re-create it, be sure to select "C++ Project" from the New Project menu.

Q: Why does Chap07/jump.c use fgets() instead of fgetln()?

A: The fgetln() function is from BSD, so it's not part of the GNU standard library. This means that it works on a Mac but not on Windows or Linux. The fgets() function is the standard way to do this and it works on all modern platforms.

Q:  When setting up the "New CDT Project Wizard" in Eclipse, I don't see a choice for the GCC toolchain (MacOSX GCC on a Mac or MinGW GCC on a Windows PC). What do I need to do?

A:  When setting up the toolchains you need to select "Executable" -> "Empty Project" under "Preferred Toolchains," and when creating a project you need to select "Executable" -> "Empty Project" under "Project type." When the setup movies were recorded, the Executable project type was first in the list. In the latest version of Eclipse it is no longer first in the list, so make sure to select it from the correct spot.

If you select Executable and still don't see the option for your toolchain, or you see it and it's greyed out, you may need to uncheck the box that says "Show project types and toolchains only if they are supported on the platform." This has been know to happen on a Windows PC where MinGW was installed but MS Visual Studio was not installed. If you uncheck this box and are able to select your toolchain, it should still work. This is a bug in Eclipse.

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