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, 23 insertions, 21 deletions

diff --git a/tree.c b/tree.c
index 8b3230e3..0c803d8e 100644
--- a/tree.c
+++ b/tree.c
@@ -537,28 +537,30 @@ static val tr_do_delete_specific(val tree, struct tree *tr, val subtree,
     return subtree;
   }
 
-  val tr_key = if3(tr->key_fn,
-                   funcall1(tr->key_fn, subtree->tn.key),
-                   subtree->tn.key);
-
-  if (if3(tr->less_fn,
-          funcall2(tr->less_fn, key, tr_key),
-          less(key, tr_key)))
   {
-    val le = subtree->tn.left;
-    return tr_do_delete_specific(tree, tr, le, subtree, key, thisnode);
-  } else if (if3(tr->equal_fn == nil,
-                 equal(key, tr_key),
-                 funcall2(tr->equal_fn, key, tr_key)))
-  {
-    uses_or2;
-    val le = subtree->tn.left;
-    val ri = subtree->tn.right;
-    return or2(tr_do_delete_specific(tree, tr, le, subtree, key, thisnode),
-               tr_do_delete_specific(tree, tr, ri, subtree, key, thisnode));
-  } else {
-    val ri = subtree->tn.right;
-    return tr_do_delete_specific(tree, tr, ri, subtree, key, thisnode);
+    val tr_key = if3(tr->key_fn,
+                     funcall1(tr->key_fn, subtree->tn.key),
+                     subtree->tn.key);
+
+    if (if3(tr->less_fn,
+            funcall2(tr->less_fn, key, tr_key),
+            less(key, tr_key)))
+    {
+      val le = subtree->tn.left;
+      return tr_do_delete_specific(tree, tr, le, subtree, key, thisnode);
+    } else if (if3(tr->equal_fn == nil,
+                   equal(key, tr_key),
+                   funcall2(tr->equal_fn, key, tr_key)))
+    {
+      uses_or2;
+      val le = subtree->tn.left;
+      val ri = subtree->tn.right;
+      return or2(tr_do_delete_specific(tree, tr, le, subtree, key, thisnode),
+                 tr_do_delete_specific(tree, tr, ri, subtree, key, thisnode));
+    } else {
+      val ri = subtree->tn.right;
+      return tr_do_delete_specific(tree, tr, ri, subtree, key, thisnode);
+    }
   }
 }