args: don't use alloca for const size cases.

* args.h (args_decl_list): This macro now handles only
constant values of N. It declares an anonyous container
struct type which juxtaposes the struc args header
with exactly N values. This is simply defined as a local
variable without alloca.
(args_decl_constsize): Like args_decl, but requiring a
constant N; implemented via args_decl_list.
(args_decl_list_dyn): New name for the old args_decl_list
which calls alloca. No places in the code depend on this
at all, except the definition of args_decl.
(args_decl): Retargeted to args_decl_list_dyn.
There is some inconsistency in the macro naming in that
args_decl_constsize depends on args_decl_list, and
args_decl depends on arg_decl_list_dyn.  This was done
to minimize diffs. Most direct uses of args_decl_list
have a constant size, but a large number of args_decl
uses do not have a constant size.

* eval.c (op_catch): Use args_decl_constsize.

* ffi.c (ffi_struct_in, ffi_struct_get, union_out):
Likewise.

* ftw.c (ftw_callback): Likewise.

* lib.c (funcall, funcall1, funcall2, funcall3,
funcall4, uniq, relate): Likewise.

* socket.c (sockaddr_in_unpack, sockaddr_in6_unpack,
sockaddr_un_unpack):
Likewise.

* stream.c (formatv): Likewise.

* struct.c (struct_from_plist, struct_from_args,
make_struct_lit): Likewise.

* sysif.c (termios_unpack): Likewise.

* time.c (broken_time_struct): Likewise.

1 files changed, 3 insertions, 3 deletions

diff --git a/socket.c b/socket.c
index dfa6cff0..e82fb96f 100644
--- a/socket.c
+++ b/socket.c
@@ -134,7 +134,7 @@ static void ipv6_scope_id_from_num(struct sockaddr_in6 *dst, val scope)
 
 static val sockaddr_in_unpack(struct sockaddr_in *src)
 {
-  args_decl(args, ARGS_MIN);
+  args_decl_constsize(args, ARGS_MIN);
   val out = make_struct(sockaddr_in_s, nil, args);
   slotset(out, addr_s, ipv4_addr_to_num(&src->sin_addr));
   slotset(out, port_s, num_fast(ntohs(src->sin_port)));
@@ -143,7 +143,7 @@ static val sockaddr_in_unpack(struct sockaddr_in *src)
 
 static val sockaddr_in6_unpack(struct sockaddr_in6 *src)
 {
-  args_decl(args, ARGS_MIN);
+  args_decl_constsize(args, ARGS_MIN);
   val out = make_struct(sockaddr_in6_s, nil, args);
   slotset(out, addr_s, ipv6_addr_to_num(&src->sin6_addr));
   slotset(out, port_s, num_fast(ntohs(src->sin6_port)));
@@ -152,7 +152,7 @@ static val sockaddr_in6_unpack(struct sockaddr_in6 *src)
 
 static val sockaddr_un_unpack(struct sockaddr_un *src)
 {
-  args_decl(args, ARGS_MIN);
+  args_decl_constsize(args, ARGS_MIN);
   val out = make_struct(sockaddr_un_s, nil, args);
   slotset(out, path_s, string_utf8(src->sun_path));
   return out;