MINOR: lua: add a compilation error message when compiled with an incompatible version
haproxy Lua support begins with Lua 5.2. In order to ease the diagnostic on
compilation error, a preprocessor error is added when an incompatible version
is used.
The compatibility is determined by the presence of LUA_VERSION_NUM and its
magic value (502 for Lua 5.2.x).
diff --git a/src/hlua.c b/src/hlua.c
index 9ded473..51e149e 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -4,6 +4,10 @@
#include <lua.h>
#include <lualib.h>
+#if !defined(LUA_VERSION_NUM) || LUA_VERSION_NUM < 502
+#error "Requires Lua 5.2 or later."
+#endif
+
#include <ebpttree.h>
#include <common/cfgparse.h>