Ouch! Turns out the code base has numerous unintended

deviations from C90, like mixed declations and
statements. GCC doesn't diagnose these without the
--pedantic flag.

* configure: GCC's --ansi flag should be spelled -ansi.

* lib.c (split_str, obj_print): Reorder declaration before statements.
(make_sym): Fix similar problem by eliminating a statement.
(funcall1, funcall2, funcall3, funcall4): Use assignment to initialize
local array with non-constant elements.  This is actually good for
performance because we only initialize those parts of the array that
we use.

* lib.h (struct func): Change functype member to unsigned,
since enum-typed bitfields are a GCC extension.

* match.c (ml_all, mf_all): Use assignments to initialize local
struct with non-constants.
(do_txeval, v_collect): Slightly revise unwinding macrology with help
of new macros to avoid mixing declarations and statements.
(spec_bind): Removed spurious semicolon from macro expansion.
(v_gather): Reorder two lines to avoid mixed decls and
statements.
(match_filter): Move declaration of ret a few lines up, ahead of
statements.

* unwind.c (uw_pop_until): New function.

* unwind.h (uw_pop_until): Declared.
(uw_mark_frame, uw_fast_return): New macros.

7 files changed, 99 insertions, 25 deletions

diff --git a/ChangeLog b/ChangeLog
index 8ab1f112..201468f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,37 @@
+2013-10-24  Kaz Kylheku  <kaz@kylheku.com>
+
+	Ouch! Turns out the code base has numerous unintended
+	deviations from C90, like mixed declations and
+	statements. GCC doesn't diagnose these without the
+	--pedantic flag.
+
+	* configure: GCC's --ansi flag should be spelled -ansi.
+
+	* lib.c (split_str, obj_print): Reorder declaration before statements.
+	(make_sym): Fix similar problem by eliminating a statement.
+	(funcall1, funcall2, funcall3, funcall4): Use assignment to initialize
+	local array with non-constant elements.  This is actually good for
+	performance because we only initialize those parts of the array that
+	we use.
+
+	* lib.h (struct func): Change functype member to unsigned,
+	since enum-typed bitfields are a GCC extension.
+
+	* match.c (ml_all, mf_all): Use assignments to initialize local
+	struct with non-constants.
+	(do_txeval, v_collect): Slightly revise unwinding macrology with help
+	of new macros to avoid mixing declarations and statements.
+	(spec_bind): Removed spurious semicolon from macro expansion.
+	(v_gather): Reorder two lines to avoid mixed decls and
+	statements.
+	(match_filter): Move declaration of ret a few lines up, ahead of
+	statements.
+
+	* unwind.c (uw_pop_until): New function.
+
+	* unwind.h (uw_pop_until): Declared.
+	(uw_mark_frame, uw_fast_return): New macros.
+
 2013-10-23  Kaz Kylheku  <kaz@kylheku.com>
 
 	* genvim.txr: Split long lines of keywords.
diff --git a/configure b/configure
index 571762d3..dece3572 100755
--- a/configure
+++ b/configure
@@ -81,7 +81,7 @@ yacc='$(cross)$(tool_prefix)$(yaccname)'
 yacc_given=
 nm='$(cross)$(tool_prefix)nm'
 opt_flags=-O2
-lang_flags='--ansi -D_XOPEN_SOURCE=2'
+lang_flags='-ansi -D_XOPEN_SOURCE=2'
 diag_flags='-Wall -Wmissing-prototypes -Wstrict-prototypes'
 debug_flags=-g
 inline=
diff --git a/lib.c b/lib.c
index 2b90b60a..35c8296b 100644
--- a/lib.c
+++ b/lib.c
@@ -2007,11 +2007,11 @@ val split_str(val str, val sep)
       const wchar_t *cstr = c_str(str);
       const wchar_t *csep = c_str(sep);
 
+      list_collect_decl (out, iter);
+
       prot1(&str);
       prot1(&sep);
 
-      list_collect_decl (out, iter);
-
       for (;;) {
         const wchar_t *psep = wcsstr(cstr, csep);
         size_t span = (psep != 0) ? psep - cstr : wcslen(cstr);
@@ -2025,8 +2025,10 @@ val split_str(val str, val sep)
         }
         break;
       }
+
       rel1(&sep);
       rel1(&str);
+
       return out;
     }
   }
@@ -2416,8 +2418,8 @@ val make_sym(val name)
 
 val gensym(val prefix)
 {
-  gensym_counter = plus(gensym_counter, one);
-  val name = format(nil, lit("~a~,04a"), prefix, gensym_counter, nao);
+  val name = format(nil, lit("~a~,04a"), prefix,
+                    gensym_counter = plus(gensym_counter, one), nao);
   return make_sym(name);
 }
 
@@ -2991,7 +2993,8 @@ val funcall1(val fun, val arg)
   type_check(fun, FUN);
 
   if (fun->f.optargs) {
-    val args[32] = { arg };
+    val args[32];
+    args[0] = arg;
     return generic_funcall(fun, args, 1);
   }
 
@@ -3028,7 +3031,9 @@ val funcall2(val fun, val arg1, val arg2)
   type_check(fun, FUN);
 
   if (fun->f.optargs) {
-    val arg[32] = { arg1, arg2 };
+    val arg[32];
+    arg[0] = arg1;
+    arg[1] = arg2;
     return generic_funcall(fun, arg, 2);
   }
 
@@ -3070,7 +3075,10 @@ val funcall3(val fun, val arg1, val arg2, val arg3)
   type_check(fun, FUN);
 
   if (fun->f.optargs) {
-    val arg[32] = { arg1, arg2, arg3 };
+    val arg[32];
+    arg[0] = arg1;
+    arg[1] = arg2;
+    arg[2] = arg3;
     return generic_funcall(fun, arg, 3);
   }
 
@@ -3116,7 +3124,11 @@ val funcall4(val fun, val arg1, val arg2, val arg3, val arg4)
   type_check(fun, FUN);
 
   if (fun->f.optargs) {
-    val arg[32] = { arg1, arg2, arg3, arg4 };
+    val arg[32];
+    arg[0] = arg1;
+    arg[1] = arg2;
+    arg[2] = arg3;
+    arg[3] = arg4;
     return generic_funcall(fun, arg, 4);
   }
 
@@ -4646,8 +4658,8 @@ val obj_print(val obj, val out)
   case STR:
     {
       const wchar_t *ptr;
-      put_char(chr('"'), out);
       int semi_flag = 0;
+      put_char(chr('"'), out);
 
       for (ptr = c_str(obj); *ptr; ptr++) {
         if (semi_flag && iswxdigit(*ptr))
diff --git a/lib.h b/lib.h
index c29eaa6d..231d830b 100644
--- a/lib.h
+++ b/lib.h
@@ -107,7 +107,7 @@ struct func {
   unsigned optargs : 7;  /* fixparam - optargs = required args */
   unsigned variadic : 1;
   unsigned : 1;
-  functype_t functype : 16;
+  unsigned functype : 16;
   val env;
   union {
     val interp_fun;
diff --git a/match.c b/match.c
index 0cd4da50..070303cf 100644
--- a/match.c
+++ b/match.c
@@ -343,8 +343,15 @@ typedef struct {
 static match_line_ctx ml_all(val bindings, val specline, val dataline,
                              val pos, val data_lineno, val file)
 {
-  match_line_ctx c = { bindings, specline, dataline, 
-                       zero, pos, data_lineno, file };
+  match_line_ctx c;
+  c.bindings = bindings;
+  c.specline = specline;
+  c.dataline = dataline;
+  c.base = zero;
+  c.pos = pos;
+  c.data_lineno = data_lineno;
+  c.file = file;
+
   return c;
 }
 
@@ -1394,11 +1401,12 @@ static val subst_vars(val spec, val bindings, val filter)
 static val do_txeval(val spec, val form, val bindings, val allow_unbound)
 {
   val ret = nil;
+  uw_mark_frame;
+  uw_catch_begin (cons(query_error_s, nil), exc_sym, exc);
 
   if (!form)
-    return nil;
+    uw_fast_return(nil);
 
-  uw_catch_begin (cons(query_error_s, nil), exc_sym, exc);
   {
     if (!form) {
       ret = form;
@@ -1847,7 +1855,12 @@ static void do_output(val bindings, val specs, val filter, val out)
 static match_files_ctx mf_all(val spec, val files, val bindings,
                               val data, val data_lineno)
 {
-  match_files_ctx c = { spec, files, car(files), bindings, data, data_lineno };
+  match_files_ctx c;
+  c.spec = spec;
+  c.files = files;
+  c.bindings = bindings;
+  c.data = data;
+  c.data_lineno = data_lineno;
   return c;
 }
 
@@ -1906,7 +1919,7 @@ typedef val (*v_match_func)(match_files_ctx *cout);
 
 #define spec_bind(specline, first_spec, spec)           \
   val specline = first(spec);                           \
-  val first_spec = first(specline);
+  val first_spec = first(specline)
 
 static val v_skip(match_files_ctx *c)
 {
@@ -2538,8 +2551,8 @@ static val v_gather(match_files_ctx *c)
         c->bindings = new_bindings;
         max_data = t;
       } else if (consp(success) && max_data != t) {
-        c->bindings = new_bindings;
         cons_bind (new_data, new_line, success);
+        c->bindings = new_bindings;
         if (gt(new_line, max_line)) {
           max_line = new_line;
           max_data = new_data;
@@ -2647,6 +2660,8 @@ static val v_collect(match_files_ctx *c)
   cnum ctimes = fixnump(times) ? c_num(times) : 0;
   cnum clines = fixnump(lines) ? c_num(lines) : 0;
   val iter;
+  uw_mark_frame;
+  uw_block_begin(nil, result);
 
   if (gap && (max || min))
     sem_error(specline, lit("~s: cannot mix :gap with :mingap or :maxgap"),
@@ -2662,9 +2677,7 @@ static val v_collect(match_files_ctx *c)
   vars = vars_to_bindings(specline, vars, c->bindings);
 
   if ((times && ctimes == 0) || (lines && clines == 0))
-    return next_spec_k;
-
-  uw_block_begin(nil, result);
+    uw_fast_return(next_spec_k);
 
   result = t;
 
@@ -3748,11 +3761,11 @@ val match_filter(val name, val arg, val other_args)
                             cons(in_arg_sym, cons(out_arg_sym, other_args))),
                        nao), nil);
   match_files_ctx c = mf_all(spec, nil, bindings, nil, num(0));
+  val ret = v_fun(&c);
+
   (void) first_spec;
   rlcp(car(spec), specline);
 
-  val ret = v_fun(&c);
-
   if (ret == nil)
     sem_error(specline, lit("filter: (~s ~s ~s) failed"), name,
               arg, out_arg_sym, nao);
diff --git a/unwind.c b/unwind.c
index e76ace02..35084a81 100644
--- a/unwind.c
+++ b/unwind.c
@@ -187,6 +187,12 @@ void uw_pop_frame(uw_frame_t *fr)
   }
 }
 
+void uw_pop_until(uw_frame_t *fr)
+{
+  while (uw_stack != fr)
+    uw_pop_frame(uw_stack);
+}
+
 uw_frame_t *uw_current_frame(void)
 {
   return uw_stack;
diff --git a/unwind.h b/unwind.h
index db8a53fa..9d584a2a 100644
--- a/unwind.h
+++ b/unwind.h
@@ -110,16 +110,25 @@ void uw_push_debug(uw_frame_t *, val func, val args,
                    val ub_p_a_pairs, val env, val data,
                    val line, val chr);
 void uw_pop_frame(uw_frame_t *);
+void uw_pop_until(uw_frame_t *);
 uw_frame_t *uw_current_frame(void);
 uw_frame_t *uw_current_exit_point(void);
 void uw_init(void);
 
 noreturn val type_mismatch(val, ...);
 
+#define uw_mark_frame                           \
+  uw_frame_t *uw_top = uw_current_frame()
+
+#define uw_fast_return(VAL)                     \
+  do {                                          \
+    uw_pop_until(uw_top);                       \
+    return VAL;                                 \
+  } while (0)
+
 #define uw_block_begin(TAG, RESULTVAR)  \
   obj_t *RESULTVAR = nil;               \
-  do                                    \
-  {                                     \
+  do {                                  \
     uw_frame_t uw_blk;                  \
     uw_push_block(&uw_blk, TAG);        \
     if (setjmp(uw_blk.bl.jb)) {         \