1#
2# Determine if the printf() functions have the %a format character.
3# This is modified from:
4# http://www.gnu.org/software/ac-archive/htmldoc/ac_cxx_have_ext_slist.html
5AC_DEFUN([AC_C_PRINTF_A],
6[AC_CACHE_CHECK([if printf has the %a format character],[llvm_cv_c_printf_a],
7[AC_LANG_PUSH([C])
8 AC_RUN_IFELSE([
9  AC_LANG_PROGRAM([[
10#include <stdio.h>
11#include <stdlib.h>
12]],[[
13volatile double A, B;
14char Buffer[100];
15A = 1;
16A /= 10.0;
17sprintf(Buffer, "%a", A);
18B = atof(Buffer);
19if (A != B)
20  return (1);
21if (A != 0x1.999999999999ap-4)
22  return (1);
23return (0);]])],
24  llvm_cv_c_printf_a=yes,
25  llvmac_cv_c_printf_a=no,
26  llvmac_cv_c_printf_a=no)
27 AC_LANG_POP([C])])
28 if test "$llvm_cv_c_printf_a" = "yes"; then
29   AC_DEFINE([HAVE_PRINTF_A],[1],[Define to have the %a format string])
30 fi
31])
32