Deprecated the emulation of '__le' using '__lt'

As hinted in the manual for Lua 5.3, the emulation of the metamethod
for '__le' using '__le' has been deprecated. It is slow, complicates
the logic, and it is easy to avoid this emulation by defining a proper
'__le' function.

Moreover, often this emulation was used wrongly, with a programmer
assuming that an order is total when it is not (e.g., NaN in
floating-point numbers).

1 files changed, 5 insertions, 3 deletions

diff --git a/lstate.h b/lstate.h
index 2a36bd96..5461b291 100644
--- a/lstate.h
+++ b/lstate.h
@@ -138,9 +138,11 @@ typedef struct CallInfo {
 #define CIST_YPCALL     (1<<3)  /* call is a yieldable protected call */
 #define CIST_TAIL       (1<<4)  /* call was tail called */
 #define CIST_HOOKYIELD  (1<<5)  /* last hook called yielded */
-#define CIST_LEQ        (1<<6)  /* using __lt for __le */
-#define CIST_FIN        (1<<7)  /* call is running a finalizer */
-#define CIST_TRAN       (1<<8)  /* 'ci' has transfer information */
+#define CIST_FIN        (1<<6)  /* call is running a finalizer */
+#define CIST_TRAN       (1<<7)  /* 'ci' has transfer information */
+#if defined(LUA_COMPAT_LT_LE)
+#define CIST_LEQ        (1<<8)  /* using __lt for __le */
+#endif
 
 /* active function is a Lua function */
 #define isLua(ci)       (!((ci)->callstatus & CIST_C))