Macro: ac_cxx_bool

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# ac_cxx_bool

## Synopsis

`AC_CXX_BOOL`

## Version

1.1.1.1 (2001/07/26) C++_Support @ ac-archive-0.5.32

## Author

Luc Maisonobe

## Description

If the compiler recognizes bool as a separate built-in type, define HAVE_BOOL. Note that a typedef is not a separate type since you cannot overload a function such that it accepts either the basic type or the typedef.

## M4 Source Code

    AC_DEFUN([AC_CXX_BOOL],
    [AC_CACHE_CHECK(whether the compiler recognizes bool as a built-in type,
    ac_cv_cxx_bool,
    [AC_LANG_SAVE
     AC_LANG_CPLUSPLUS
     AC_TRY_COMPILE([
    int f(int  x){return 1;}
    int f(char x){return 1;}
    int f(bool x){return 1;}
    ],[bool b = true; return f(b);],
     ac_cv_cxx_bool=yes, ac_cv_cxx_bool=no)
     AC_LANG_RESTORE
    ])
    if test "$ac_cv_cxx_bool" = yes; then
      AC_DEFINE(HAVE_BOOL,,[define if bool is a built-in type])
    fi
    ])