diff options
Diffstat (limited to 'acinclude.m4')
| -rwxr-xr-x[-rw-r--r--] | acinclude.m4 | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/acinclude.m4 b/acinclude.m4 index 539322870..dd5d896bc 100644..100755 --- a/acinclude.m4 +++ b/acinclude.m4 @@ -3243,3 +3243,29 @@ AC_DEFUN([CURL_MAC_CFLAGS], [ fi ]) + + +dnl CURL_SUPPORTS_BUILTIN_AVAILABLE +dnl +dnl Check to see if the compiler supports __builtin_available. This built-in +dnl compiler function first appeared in Apple LLVM 9.0.0. It's so new that, at +dnl the time this macro was written, the function was not yet documented. Its +dnl purpose is to return true if the code is running under a certain OS version +dnl or later. + +AC_DEFUN([CURL_SUPPORTS_BUILTIN_AVAILABLE], [ + AC_MSG_CHECKING([to see if the compiler supports __builtin_available()]) + AC_COMPILE_IFELSE([ + AC_LANG_PROGRAM([[ +#include <stdlib.h> + ]],[[ + if (__builtin_available(macOS 10.8, iOS 5.0, *)) {} + ]]) + ],[ + AC_MSG_RESULT([yes]) + AC_DEFINE_UNQUOTED(HAVE_BUILTIN_AVAILABLE, 1, + [Define to 1 if you have the __builtin_available function.]) + ],[ + AC_MSG_RESULT([no]) + ]) +]) |