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   AX_CFLAGS_WARN_ALL   [(shellvar[, default[, action-if-found[, action-if-not-found]]])]
AX_CXXFLAGS_WARN_ALL [(shellvar[, default[, action-if-found[, action-if-not-found]]])]
AX_FCFLAGS_WARN_ALL  [(shellvar[, default[, action-if-found[, action-if-not-found]]])]


Specify compiler options that enable most reasonable warnings. For the GNU Compiler Collection (GCC), for example, it will be "-Wall". The result is added to shellvar, one of CFLAGS, CXXFLAGS or FCFLAGS if the first parameter is not specified.

Each of these macros accepts the following optional arguments:

  - $1 - shellvar
      shell variable to use (CFLAGS, CXXFLAGS or FCFLAGS if not
      specified, depending on macro)
  - $2 - default
      value to use for flags if compiler vendor cannot be determined (by
      default, "")
  - $3 - action-if-found
      action to take if the compiler vendor has been successfully
      determined (by default, add the appropriate compiler flags to
  - $4 - action-if-not-found
      action to take if the compiler vendor has not been determined or
      is unknown (by default, add the default flags, or "" if not
      specified, to shellvar)

These macros use AX_COMPILER_VENDOR to determine which flags should be returned for a given compiler. Not all compilers currently have flags defined for them; patches are welcome. If need be, compiler flags may be made language-dependent: use a construct like the following:

   [vendor_name], [m4_if(_AC_LANG_PREFIX,[C],   VAR="--relevant-c-flags",dnl
                  m4_if(_AC_LANG_PREFIX,[CXX], VAR="--relevant-c++-flags",dnl
                  m4_if(_AC_LANG_PREFIX,[FC],  VAR="--relevant-fortran-flags",dnl
                  VAR="$2"; FOUND="no")))],

Note: These macros also depend on AX_PREPEND_FLAG.

Source Code

Download the latest version of ax_cflags_warn_all.m4 or browse the macro’s revision history.


Copyright © 2008 Guido U. Draheim
Copyright © 2010 Rhys Ulerich
Copyright © 2018 John Zaitseff

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