From f72fa1121f2571aba9f16f95d58d8e915965d765 Mon Sep 17 00:00:00 2001
From: Kaz Kylheku <kaz@kylheku.com>
Date: Tue, 8 Sep 2015 06:43:11 -0700
Subject: Random states of type random-state, not *random-state*.

* lib.c (compat_fixup): Call rand_compat_fixup.

* rand.c (random_state_var_s): New global symbol variable.
(rand_compat_fixup): New static function.
(rand_init): Initialize random_state_var_s by intering
the earmuffed symbol *random-state*. Initialize random_state_s
to the non-earmuffed symbol random-state.

* rand.h (random_state_var_s): Declared.
(random_state): Macro updated to look up the special
variable using random_state_var_s, rather than random_state_s.
(rand_compat_fixup): Declared.
---
 lib.c  |  1 +
 rand.c | 17 ++++++++++++++---
 rand.h |  5 +++--
 txr.1  |  8 ++++++++
 4 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/lib.c b/lib.c
index d96ab8b2..84988206 100644
--- a/lib.c
+++ b/lib.c
@@ -7762,6 +7762,7 @@ int compat_fixup(int compat_ver)
   }
 
   eval_compat_fixup(compat_ver);
+  rand_compat_fixup(compat_ver);
   return 0;
 }
 
diff --git a/rand.c b/rand.c
index b6ccdda2..b127dae0 100644
--- a/rand.c
+++ b/rand.c
@@ -44,6 +44,7 @@
 #include "signal.h"
 #include "unwind.h"
 #include "arith.h"
+#include "txr.h"
 #include "rand.h"
 #include "eval.h"
 
@@ -62,7 +63,7 @@ struct rand_state {
   unsigned cur;
 };
 
-val random_state_s;
+val random_state_s, random_state_var_s;
 
 static struct cobj_ops random_state_ops = cobj_ops_init(eq,
                                                         cobj_print_op,
@@ -261,8 +262,18 @@ val rnd(val modulus, val state)
   return random(state, modulus);
 }
 
+void rand_compat_fixup(int compat_ver)
+{
+  if (compat_ver <= 114) {
+    loc l = lookup_var_l(nil, random_state_var_s);
+    random_state_s = random_state_var_s;
+    set(l, make_random_state(num_fast(42)));
+  }
+}
+
 void rand_init(void)
 {
-  random_state_s = intern(lit("*random-state*"), user_package);
-  reg_var(random_state_s, make_random_state(num_fast(42)));
+  random_state_var_s = intern(lit("*random-state*"), user_package);
+  random_state_s = intern(lit("random-state"), user_package);
+  reg_var(random_state_var_s, make_random_state(num_fast(42)));
 }
diff --git a/rand.h b/rand.h
index 23c4167a..d68be1f9 100644
--- a/rand.h
+++ b/rand.h
@@ -24,11 +24,12 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#define random_state (deref(lookup_var_l(nil, random_state_s)))
-extern val random_state_s;
+#define random_state (deref(lookup_var_l(nil, random_state_var_s)))
+extern val random_state_s, random_state_var_s;
 val make_random_state(val seed);
 val random_state_p(val obj);
 val random_fixnum(val state);
 val random(val state, val modulus);
 val rnd(val modulus, val state);
+void rand_compat_fixup(int compat_ver);
 void rand_init(void);
diff --git a/txr.1 b/txr.1
index 2192b870..bac8d8e6 100644
--- a/txr.1
+++ b/txr.1
@@ -33297,6 +33297,7 @@ selects the behaviors described below for version 105, but not those for 102.
 .cble
 
 The new format omits the program name prefix and parentheses.
+
 Also, the
 .code kill
 function returned an integer, obtained from the return
@@ -33304,6 +33305,13 @@ value of the underlying C function, rather than converting
 that value to a boolean. The old behavior was not documented,
 and 114 compatibility restores it.
 
+Lastly, prior to 115, random state objects were of type
+.code *random-state*
+(the same symbol as the special variable name)
+rather than of type
+.codn random-state .
+This is a bug whose behavior is simulated by 114 compatibility.
+
 .IP 113
 Version 113 is the last version in which the
 .codn stat ,
-- 
cgit v1.2.3