7.3.2.6 Warnings

  • -Wall

    Show all warnings.

  • -Werror

    Show warnings as errors.

  • -fsyntax-only

    Check the code for syntax errors, but don't do anything beyond that.

  • -pedantic

    Issue all the warnings demanded by strict ISO C. Reject all programs using forbidden extensions and other programs that do not follow ISO C. Valid ISO C programs should compile properly with or without this option (though a rare few will require -ansi or a -std option specifying the required version of ISO C). However, some GNU extensions and usual C features are supported without this option and rejected with this option.

  • -pedantic-errors

    Pedantic warnings are produced as errors.

  • -w

    Inhibit all warning messages.