$NetBSD: patch-configure,v 1.2 2024/04/22 09:59:20 he Exp $

Build fix for NetBSD, where:
* <alloca.h> does not exist but alloca(3) is available in <stdlib.h> instead
* <sys/select.h> is not automatically visible
* probe for gnu99 not c99 for more universal alloca() availability

--- configure.orig	2016-05-03 06:12:05.000000000 +0000
+++ configure
@@ -12352,10 +12352,10 @@ _ACEOF
 $as_echo "$ac_v_func" >&6; }
 
 # C99 support (mandatory)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $CC supports -std=c99 flags" >&5
-$as_echo_n "checking if $CC supports -std=c99 flags... " >&6; }
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $CC supports -std=gnu99 flags" >&5
+$as_echo_n "checking if $CC supports -std=gnu99 flags... " >&6; }
     SAVE_CFLAGS="$CFLAGS"
-    CFLAGS="-std=c99"
+    CFLAGS="-std=gnu99"
     cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -12377,9 +12377,9 @@ rm -f core conftest.err conftest.$ac_obj
     { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_try_cflags_ok" >&5
 $as_echo "$ac_cv_try_cflags_ok" >&6; }
     if test x"$ac_cv_try_cflags_ok" = x"yes"; then
-        CFLAGS="${CFLAGS} -std=c99"
+        CFLAGS="${CFLAGS} -std=gnu99"
     else
-        as_fn_error $? "support for C99 (-std=c99) required" "$LINENO" 5
+        as_fn_error $? "support for GNU C99 (-std=gnu99) required" "$LINENO" 5
     fi
 
 # Library suffix
@@ -12561,7 +12561,7 @@ fi
 
 done
 
-for ac_header in malloc.h dlfcn.h regex.h sys/cdefs.h sys/socket.h
+for ac_header in alloca.h malloc.h dlfcn.h regex.h sys/cdefs.h sys/socket.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"
@@ -12587,7 +12587,7 @@ fi
 
 done
 
-for ac_header in sys/mman.h sys/wait.h sys/resource.h sys/time.h
+for ac_header in sys/mman.h sys/wait.h sys/resource.h sys/select.h sys/time.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"