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c++xcodemigrationclangcompiler-options

clang compiler options aren't documented?

For the sake of migrating compiler options to ARM using Xcode, I'm looking for a comprehensive documentation for clang c++ compiler/linker options. The closest I could get was this page, however:

  1. Many options aren't explained, e.g. -arch, -arch_errors_fatal, -sub_umbrella and many more.
  2. There are options in the Xcode command line that are missing in this doc, e.g. -Wno-four-char-constants, -Wshorten-64-to-32 etc.

Is there any place where I could find a full documentation with generous explanations for each option? Please note, I don't need the meaning of the options I gave here as examples, only for a comprehensive reference.

Solution

  • I think that in general, you need to refer to Clang documentation and to the Cross-compilation using Clang.

    Update:

    • If you cannot find the argument you need, please go to the bottom of the page to Search Page.
    • Paste the argument and press "Search".
    • If the argument is supported, you will see its description.

    For example, if you look for -arch_errors_fatal it will show this:

    Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|text).

    -ansi, --ansi -arch -arch_errors_fatal

    It is not very descriptive but on the top of the same page, you can see:

    Introduction This page lists the command line arguments currently supported by the GCC-compatible clang and clang++ drivers.

    Hence, this specific flag was added for compatibility with the GCC, so you need to look for it in the GCC's documentation.

    So you do the following:

    • man gcc.
    • Press /, paste -arch_errors_fatal, and press Enter. This is the search in the man page.
    • press n until you find the relevant information. For this specific flag it will show you:

    -arch_errors_fatal Cause the errors having to do with files that have the wrong architecture to be fatal.

    I forgot that MacOS comes without GCC nowadays, so you can lookup the GCC manual page online.

    Looking for information about open-source tools might be not very straight-forward but yet feasible.

    Hope it helps.