lua_pushcfunction (lua 5.3) seems to be able to throw error, contrary to docs

[Andrew Gierth <andrew@...>]

I may be misreading this, but:

5.3 docs say that lua_pushcfunction cannot throw error (it's tagged with
[-0, +1, -]).

But reading the code, it seems to be able to throw an error on this
path:

lua_pushcfunction (macro)
 calls lua_pushcclosure with n==0
  calls luaC_checkGC  (even when n==0)
   calls luaC_step
    calls runafewfinalizers
     calls GCTM with propagateerrors==1
      calls luaD_throw to propagate an error from a finalizer

This looks like a problem in the code to me: wouldn't it make more sense
to put the luaC_checkGC call in lua_pushcclosure inside the else
clause?

But if the behavior of the code is regarded as being correct, it seems a
rather critical documentation error... I just wrote a whole lot of code
relying on the documented behavior, and got a very nasty surprise.

-- 
Andrew.