| # |
| # Determine if the printf() functions have the %a format character. |
| # This is modified from: |
| # http://www.gnu.org/software/ac-archive/htmldoc/ac_cxx_have_ext_slist.html |
| AC_DEFUN([AC_C_PRINTF_A], |
| [AC_CACHE_CHECK([if printf has the %a format character],[llvm_cv_c_printf_a], |
| [AC_LANG_PUSH([C]) |
| AC_RUN_IFELSE([ |
| AC_LANG_PROGRAM([[ |
| #include <stdio.h> |
| #include <stdlib.h> |
| ]],[[ |
| volatile double A, B; |
| char Buffer[100]; |
| A = 1; |
| A /= 10.0; |
| sprintf(Buffer, "%a", A); |
| B = atof(Buffer); |
| if (A != B) |
| return (1); |
| if (A != 0x1.999999999999ap-4) |
| return (1); |
| return (0);]])], |
| llvm_cv_c_printf_a=yes, |
| llvmac_cv_c_printf_a=no, |
| llvmac_cv_c_printf_a=no) |
| AC_LANG_POP([C])]) |
| if test "$llvm_cv_c_printf_a" = "yes"; then |
| AC_DEFINE([HAVE_PRINTF_A],[1],[Define to have the %a format string]) |
| fi |
| ]) |
