编译OpenCV V3.1 for iOS失败：找不到install_name_tool求助

Hey there, sorry to hear you're stuck on this error after successfully building OpenCV 3.4 before—let's break down the likely fixes to get you back on track:

• Verify Xcode Command Line Tools are properly installed
  install_name_tool is part of Xcode's core command line utilities, so this error usually means they're missing or misconfigured.
  First, run this in your terminal to install or repair the tools:

  xcode-select --install
  

  If they're already installed, reset the path to ensure it points to the correct Xcode instance:

  xcode-select --reset
  

  Confirm the tool is detectable by running:

  which install_name_tool
  

  You should see a path like /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/install_name_tool. If not, your Xcode installation might be corrupted—try reinstalling Xcode.

• Add the toolchain path to your environment
  Sometimes your PATH variable doesn't include the directory where install_name_tool lives. Temporarily add it before compiling with:

  export PATH="/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin:$PATH"
  

  Then re-run your OpenCV compilation commands.

• Adjust CMake flags for OpenCV 3.1's older build system
  OpenCV 3.1 uses an older CMake configuration compared to 3.4, which might not auto-detect the Xcode toolchain correctly. Try explicitly specifying the toolchain and SDK paths in your CMake command:

  cmake -DCMAKE_OSX_SYSROOT=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk \
        -DCMAKE_C_COMPILER=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang \
        -DCMAKE_CXX_COMPILER=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ \
        # Add your other OpenCV 3.1 build flags here
  

• Check Xcode version compatibility
  OpenCV 3.1 is quite old (released in 2016), so it might not play nicely with modern Xcode versions (Xcode 10+). Since you had success with 3.4 (which is newer), try downgrading to an Xcode version that's compatible with 3.1 (like Xcode 8 or 9) and see if the build completes.

内容的提问来源于stack exchange，提问作者Amy Lin