$NetBSD: patch-src_cache.cc_configure.ac,v 1.1 2017/09/15 22:18:00 ast Exp $

* Compile with pre-2016/12/16 v1.36 dirent.h on NetBSD

--- configure.ac.orig	2017-03-06 10:29:41.000000000 +0100
+++ configure.ac	2017-09-15 23:47:38.595038637 +0200
@@ -45,6 +45,27 @@
 Please install pkg-config and re-run autoconf.])
 ])
 
+dnl Check scandir prototype in dirent.h (NetBSD pre-2016/12/16 v1.36)
+AC_MSG_CHECKING([if scandir's compar() expects const void * pointers])
+AC_LANG_WERROR
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <dirent.h>]],
+  [[
+    const char *dirname;
+    struct dirent ***namelist;
+    int (*f_select)(const struct dirent *);
+    int (*f_compar)(const void *, const void *);
+    scandir(dirname, namelist, f_select, f_compar);
+  ]])],
+   [
+     AC_MSG_RESULT([yes])
+     AC_DEFINE_UNQUOTED([SCANDIR_COMPAR_USES_CONST_VOID_POINTER], 1, [Define to 1 if you have to use const void * with scandir's compar() function, to 0 if you are using the IEEE Std 1003.1 standard const struct dirent **.])
+   ],
+   [
+     AC_MSG_RESULT([no])
+     AC_DEFINE_UNQUOTED([SCANDIR_COMPAR_USES_CONST_VOID_POINTER], 0, [Define to 1 if you have to use const void * with scandir's compar() function, to 0 if you are using the IEEE Std 1003.1 standard const struct dirent **.])
+   ]
+)
+
 dnl Poppler checking
 PKG_CHECK_MODULES(poppler_cpp, poppler-cpp)
 AC_SUBST(poppler_cpp_CFLAGS)