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, 5 insertions, 5 deletions

diff --git a/ffi.c b/ffi.c
index a383c831..767d7a9b 100644
--- a/ffi.c
+++ b/ffi.c
@@ -509,17 +509,17 @@ static val ffi_void_get(struct txr_ffi_type *tft, mem_t *src, val self)
 static void ffi_simple_release(struct txr_ffi_type *tft, val obj,
                                mem_t *dst, val self)
 {
+  mem_t **loc = coerce(mem_t **, dst);
   (void) tft;
   (void) obj;
   (void) self;
-  mem_t **loc = coerce(mem_t **, dst);
   free(*loc);
   *loc = 0;
 }
 
 #if __i386__ || __x86_64__ || __PPC64__ || __ARM_FEATURE_UNALIGNED
 
-#define align_sw_get(type, src)
+#define align_sw_get(type, src) enum { dummy ## __LINE__ }
 #define align_sw_end
 #define align_sw_put_end
 #define align_sw_put(type, dst, expr) (expr)
@@ -531,7 +531,7 @@ static void ffi_simple_release(struct txr_ffi_type *tft, val obj,
   const size_t sz = sizeof (type);                                      \
   mem_t *src_prev = src;                                                \
   mem_t *buf = al ? src : convert(mem_t *, alloca(sz));                 \
-  mem_t *src = al ? buf : (memcpy(buf, src_prev, sz), buf);
+  mem_t *src = al ? buf : (memcpy(buf, src_prev, sz), buf)
 
 #define align_sw_end                                                    \
 }
@@ -557,8 +557,8 @@ static void ffi_simple_release(struct txr_ffi_type *tft, val obj,
 #if HAVE_I8
 static void ffi_i8_put(struct txr_ffi_type *tft, val n, mem_t *dst, val self)
 {
-  (void) tft;
   i8_t v = c_i8(n, self);
+  (void) tft;
   *coerce(i8_t *, dst) = v;
 }
 
@@ -571,8 +571,8 @@ static val ffi_i8_get(struct txr_ffi_type *tft, mem_t *src, val self)
 
 static void ffi_u8_put(struct txr_ffi_type *tft, val n, mem_t *dst, val self)
 {
-  (void) tft;
   u8_t v = c_u8(n, self);
+  (void) tft;
   *coerce(u8_t *, dst) = v;
 }