macOS Catalina 10.15.5编译OMNeT++5.6.2时Qt相关错误求助

I've run into similar compatibility headaches between OMNeT++'s bundled Qt and macOS Catalina's compiler before. Let's break down what's going on and walk through actionable fixes:

What's Causing This? #

The error no template named 'is_same' in namespace 'QtPrivate' stems from a mismatch between the Qt version bundled with OMNeT++ 5.6.2 and the Clang compiler in Catalina's Command Line Tools. The QtPrivate namespace's is_same template isn't being properly recognized by the newer compiler, which correctly notes that std::is_same is available instead.

Fix Options (Ordered by Ease & Reliability) #

Option 1: Manually Patch the Qt Header Files #

Since errors are isolated to specific Qt headers, we can directly fix the references:

• Open the problematic header files in a text editor:
  • /Users/kimminwoo/Desktop/omnetpp-5.6.2/tools/macosx/include/QtCore/qtimer.h
  • /Users/kimminwoo/Desktop/omnetpp-5.6.2/tools/macosx/include/QtWidgets/qmenu.h
• Replace all instances of QtPrivate::is_same with std::is_same in both files
• Save the changes, then re-run your build command:

  make -j4
  

Option 2: Use System Qt Instead of OMNeT++'s Bundled Version #

If patching feels too hacky, switch to a system-installed Qt 5 (OMNeT++ 5.6.2 doesn't support Qt 6):

1. Install Qt 5 via Homebrew:

   brew install qt@5
   

2. Set up environment variables to point OMNeT++ to the system Qt:

   export PATH="/usr/local/opt/qt@5/bin:$PATH"
   export LDFLAGS="-L/usr/local/opt/qt@5/lib"
   export CPPFLAGS="-I/usr/local/opt/qt@5/include"
   

3. Re-configure OMNeT++ and rebuild from scratch:

   cd omnetpp-5.6.2
   ./configure
   make clean
   make -j4
   

Option 3: Downgrade Command Line Tools #

Catalina's newer Command Line Tools have stricter C++ standard enforcement that clashes with OMNeT++'s bundled Qt. Try downgrading to a compatible version:

1. Uninstall the current tools:

   sudo rm -rf /Library/Developer/CommandLineTools
   

2. Install the Command Line Tools for Xcode 11.7 (it's fully compatible with macOS 10.15.5)
3. Re-run your build command after installation completes:

   make -j4
   

Verify the Fix #

Once the build finishes without errors, confirm everything works by launching the OMNeT++ IDE:

omnetpp

If the IDE opens successfully, your installation is fully functional.

内容的提问来源于stack exchange，提问作者Minwoo Kim