Re: libffi 3.2.1 and master, can't build with Visual Studio 2012

[Richard Henderson <rth@redhat.com>]

On 11/18/2014 04:23 PM, Grégory Pakosz wrote:
> ​Hello,
> 
> I would like to inform you it's not possible to build libffi 3.2.1 with Visual Studio 2012 anymore as it's not a C99 compiler.
> 
> In src/x86/ffi.c, 
> 
>   - src/x86/ffi.c doesn't compile because
>     - commit 098dca6b31e declares "size_t z" variables not at the beginning of blocks which is possible in C99 only
>     - commit 5d6340ef2cf8 moves "int i" variable declaration from beginning to middle of block
>     - this appears to be fixed in master by commit b21ec1ce783​ though

These are simply oversights that can easily be fixed.

> static const struct abi_params abi_params[FFI_LAST_ABI] = {
>   [FFI_SYSV] = { 1, 0 },
>   [FFI_THISCALL] = { 1, 1, { R_ECX } },
>   [FFI_FASTCALL] = { 1, 2, { R_ECX, R_EDX } },
>   [FFI_STDCALL] = { 1, 0 },
>   [FFI_PASCAL] = { -1, 0 },
>   [FFI_REGISTER] = { -1, 3, { R_EAX, R_EDX, R_ECX } },
>   [FFI_MS_CDECL] = { 1, 0 }
> };

This one's tricky, without simply forcing X86 an X86_WIN32 to have the same
ffi_abi enumeration.  Currently, while they have the same symbols, the symbols
have different values.  So *not* using designated initializers is hard.

I suppose we could fill in the values at runtime from a switch statement,
but read-only data appeals to me...

And all of that's moot without re-porting the assembly back to masm, which I
was not looking forward to doing.

I have downloaded the recently released gratis VS 2013 Community, but I havn't
yet looked into it enough to figure out how to actually do things with it.
Do I really have to create some sort of project to get things to build, or
is there a command-line compiler included?

How are you building libffi with VS?


r~