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.

1 files changed, 11 insertions, 2 deletions

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)) {         \