compat: fix glaringly broken init-time handling.

We are doing numerous compat_ver checks in various init
functions, to enact alternative symbol registrations. Only
problem is, compat_ver is always zero during initialization;
it is not set until the -C option is processed in txr_main.

Registrations must be fixed up after initialization;
that's what the compat_fixup mechanism is for.

This is an long-standing problem which affects compatibility
operation going back over 150 versions.

* arith.c (arith_init): Move compat logic to
arith_compat_fixup.
(arith_compat_fixup): New function.

* arith.h (arith_compat_fixup): Declared.

* eval.c (eval_init): Move compat logic to eval_compat_fixup.

* ffi.c (ffi_init): Move compat logic to ffi_compat_fixup.
(ffi_compat_fixup): New function.

* ffi.h (ffi_compat_fixup): Declared.

* regex.c (regex_init): Move compat logic to
regex_compat_fixup.
(regex_compat_fixup): New function.

* regex.h (regex_compat_fixup): Declared.

* stream.c (stream_init): Move compat logic to
stream_compat_fixup.
(stream_compat_fixup): New function.

* stream.h (stream_compat_fixup): Declared.

* struct.c (struct_init): Move compat logic to
struct_compat_fixup.
(struct_compat_fixup): New function.

* struct.h (stream_compat_fixup): Declared.

* lib.c (compat_fixup): Call arith_compat_fixup,
ffi_compat_fixup, regex_compat_fixup, stream_compat_fixup and
struct_compat_fixup.

1 files changed, 14 insertions, 7 deletions

diff --git a/regex.c b/regex.c
index e9567221..58e6d126 100644
--- a/regex.c
+++ b/regex.c
@@ -3354,16 +3354,12 @@ void regex_init(void)
   reg_fun(intern(lit("search-regex"), user_package), func_n4o(search_regex, 2));
   reg_fun(intern(lit("range-regex"), user_package), func_n4o(range_regex, 2));
   reg_fun(intern(lit("search-regst"), user_package), func_n4o(search_regst, 2));
-  reg_fun(intern(lit("match-regex"), user_package),
-          func_n3o((opt_compat && opt_compat <= 150) ?
-                   match_regex : match_regex_len, 2));
+  reg_fun(intern(lit("match-regex"), user_package), func_n3o(match_regex_len, 2));
   reg_fun(intern(lit("match-regst"), user_package), func_n3o(match_regst, 2));
   reg_fun(intern(lit("match-regex-right"), user_package),
-          func_n3o((opt_compat && opt_compat <= 150) ?
-                   match_regex_right_old : match_regex_right, 2));
+          func_n3o(match_regex_right, 2));
   reg_fun(intern(lit("match-regst-right"), user_package),
-          func_n3o((opt_compat && opt_compat <= 150) ?
-                   match_regst_right_old : match_regst_right, 2));
+          func_n3o(match_regst_right, 2));
   reg_fun(intern(lit("regex-prefix-match"), user_package),
           func_n3o(regex_prefix_match, 2));
   reg_fun(intern(lit("regsub"), user_package), func_n3(regsub));
@@ -3395,6 +3391,17 @@ void regex_init(void)
   init_special_char_sets();
 }
 
+void regex_compat_fixup(int compat_ver)
+{
+  if (compat_ver <= 150) {
+    reg_fun(intern(lit("match-regex"), user_package), func_n3o(match_regex, 2));
+    reg_fun(intern(lit("match-regex-right"), user_package),
+            func_n3o(match_regex_right_old, 2));
+    reg_fun(intern(lit("match-regst-right"), user_package),
+            func_n3o(match_regst_right_old, 2));
+  }
+}
+
 void regex_free_all(void)
 {
   char_set_destroy(space_cs, 1);