Macro: ac_c_var_func

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# ac_c_var_func

## Synopsis

`AC_C_VAR_FUNC`

## Version

1.1.1.1 (2001/07/26) C_Support @ ac-archive-0.5.32

## Author

Christopher Currie <christopher@currie.com>

## Description

This macro tests if the C complier supports the C9X standard __func__ indentifier.

The new C9X standard for the C language stipulates that the identifier __func__ shall be implictly declared by the compiler as if, immediately following the opening brace of each function definition, the declaration

`static const char __func__[] = "function-name";`

appeared, where function-name is the name of the function where the __func__ identifier is used.

## M4 Source Code

    AC_DEFUN([AC_C_VAR_FUNC],
    [AC_REQUIRE([AC_PROG_CC])
    AC_CACHE_CHECK(whether $CC recognizes __func__, ac_cv_c_var_func,
    AC_TRY_COMPILE(,
    [int main() {
    char *s = __func__;
    }],
    AC_DEFINE(HAVE_FUNC,,
    [Define if the C complier supports __func__]) ac_cv_c_var_func=yes,
    ac_cv_c_var_func=no) )
    ])dnl