Eliminate declaration-after-statement everywhere.

The use of -ansi doesn't by itself diagnose instances of some
constructs we don't want in the project, like mixed
declarations and statements.

* configure (diag_flags): Add -Werror=declaration-after-statement.
This is C only, so filter it out for C++.
Also add -Werror=vla.

* HACKING: Update inaccurate statements about what dialect we
are using. TXR isn't pure C90: some GCC extensions are used.
We even use long long if the configure script detects it as
working, and some C99 library features.

* buf.c (replace_buf, buf_list): Fix by reordering.

* eval.c (op_dohash, op_load_time_lit): Fix by reordering.

* ffi.c (ffi_simple_release): Fix by reordering.
(align_sw_get): Fix empty macro to expand to dummy declaration
so a semicolon after it isn't interpreted as a statement.
On platforms with alignment, remove a semicolon from the macro
so that it requires one.
(ffi_i8_put, ffi_u8_put): Fix by reordering.

* gc.c (gc_init): Fix with extra braces.

* hash.c (hash_init): Fix by reordering.

* lib.c (list_collect_revappend, sub_iter, replace_str,
replace_vec, mapcar_listout, mappend, mapdo, window_map_list,
subst): Fix by reordering.
(gensym, find, rfind, pos, rpos, in, search_common): Fix by
renaming optional argument and using declaration instead of
assignment.

* linenoise/linenoise.c (edit_in_editor): Fix by reordering.

* parser.c (is_balanced_line): Fix by reordering.

* regex.c (nfa_count_one, print_rec): Fix by reordering.

* signal.c (sig_mask): Fix by reordering.

* stream.c (get_string): Fix by renaming optional argument and
using declaration instead of assignment.

* struct.c (lookup_static_slot_desc): Fix by turning mutated
variable into block local.
(umethod_args_fun): Fix by reordering.
(get_special_slot): Fix by new scope via braces.

* sysif.c (usleep_wrap): Fix by new scope via braces.
(setrlimit_wrap): Fix by new scope via braces.

* time.c (time_string_meth, time_parse_meth): Fix by reordering.

* tree.c (tr_do_delete_spec): Fix by new scope via braces.

* unwind.h (uw_block_beg): New macro which doesn't define
RESULTVAR but expects it to refers to an existing one.
(uw_block_begin): Replace do while (0) with enum trick
so that we have a declaration that requires a semicolon,
rather than a statement, allowing declarations to follow.
(uw_match_env_begin): Now opens a scope and features the
same enum trick as in uw_block_begin.
This fixes a declaration-follows-statement issue in
the v_output function in match.c.
(uw_match_env_end): Closes scope opened by uw_match_env_begin.

* unwind.c (revive_cont): Fix by introducing variable, and
using new uw_block_beg macro.

* vm.c (vm_execute_closure): Fix using combination of local
variable and reordering.

1 files changed, 2 insertions, 2 deletions

diff --git a/stream.c b/stream.c
index 34609f87..ebbb7e19 100644
--- a/stream.c
+++ b/stream.c
@@ -4173,11 +4173,11 @@ struct strm_ctx *get_ctx(val stream)
   return s->ctx;
 }
 
-val get_string(val stream_in, val nchars, val close_after_p)
+val get_string(val stream_in, val nchars_in, val close_after_p)
 {
   val stream = default_arg_strict(stream_in, std_input);
   val strstream = make_string_output_stream();
-  nchars = default_null_arg(nchars);
+  val nchars = default_null_arg(nchars_in);
   val ch;
 
   if (nchars) {