Re: Building luaffifb with MSVC

[Dibyendu Majumdar <mobile@...>]

Steven Johnson wrote:

>>> I seem to recall the C namespace just getting absorbed into another one
>>> rather than being outright missing. This sounds like it might be a
>>> simple problem (wrong table index? maybe an off-by-one caused by some
>>> platform defines?) but I ended up getting distracted before looking
>>> into it.

I have made some progress with this.

First problem appears to be that we need an additional MSVC compiler
define - as implemented in LuaJIT
(https://github.com/LuaJIT/LuaJIT/commit/02b4b1e55633c36f370058e7601c77ba561e2c8a).
This has solved the issue of finding ffi.C.sprintf).

Secondly, on Windows a symbol loaded by ffi.load() does not go into
global namespace, whereas this works on Posix environment, but only
supposed to happen if a second argument is supplied to ffi.load - see
here (http://luajit.org/ext_ffi_api.html). There is possibly a bug in
luaffifb where symbols are perhaps being loaded into global namespace
when they should not be. This explains why on Windows you need to
access the library module in the dlls table to access functions in the
libtest module. Btw this appears to be a regression in luaffifb - i.e.
original code does not attempt to access symbols in libtest using
ffi.C.

Next issue is that on Windows <complex.h> is not ISO C compliant - and
the check for this was incorrect (actually also a regression from
luaffi where it is correct).

Fourth issue is the use of %p in some tests - unfortunately there is
no defined output format for %p, and on Windows this is different.
After fixing this I found an issue (possibly a bug) where float
arguments are not being passed correctly ... to be investigated.

Fixes are all in my repository: https://github.com/dibyendumajumdar/ravi-ffi

I cannot test all this on Linux right now as I am working remotely ,
but on Mac OSX the tests passed so I assume they would also pass on
Linux.

Windows version is failing towards the end due to the potential bug
with passing float arguments.

Regards
Dibyendu