From ca92cfd3622c52ab1b76ff780a66a169a74dc99c Mon Sep 17 00:00:00 2001
From: Javier Peletier <jpeletier@users.noreply.github.com>
Date: Tue, 15 Jan 2019 17:06:11 +0100
Subject: [PATCH] fix number2integer conversion for floating-point builds
(#2605)
---
components/lua/luaconf.h | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/components/lua/luaconf.h b/components/lua/luaconf.h
index 67ac3503..e5cdf041 100644
--- a/components/lua/luaconf.h
+++ b/components/lua/luaconf.h
@@ -702,8 +702,18 @@ union luai_Cast { double l_d; long l_l; };
/* this option always works, but may be slow */
#else
-#define lua_number2int(i,d) ((i)=(int)(d))
-#define lua_number2integer(i,d) ((i)=(lua_Integer)(d))
+
+#ifdef LUA_NUMBER_INTEGRAL
+
+#define lua_number2int(i, d) ((i) = (int)(d))
+#define lua_number2integer(i, d) ((i) = (lua_Integer)(d))
+
+#else // for floating-point builds, cast to a larger integer first to avoid undefined behavior on overflows.
+
+#define lua_number2int(i, d) ((i) = (int)(long long)(d))
+#define lua_number2integer(i, d) ((i) = (lua_Integer)(long long)(d))
+
+#endif // LUA_NUMBER_INTEGRAL
#endif