Wren does not compile in 32bits (mingw/windows)

[wren-lang]

Wren does not compile in 32bits (mingw/windows)

[munificent]

Interesting. I wonder if we need another cast in the middle there to explicitly truncate it down to 32 bits. I can't repro this locally, but I can explain what's happening if that will help you look into this. Wren stores all values as a union of a Nan-tagged double and a 64-bit uint. The .bits gets the value as a 64-bit uint. The & ~(SIGN_BIT | QNAN) masks off all of the Nan stuff, leaving a 32-bit pointer stored in the rightmost bits of the 32-bit uint. Then we cast that to a pointer.

Can you try changing that line to:

#define AS_OBJ(value) ((Obj*)(uint32_t)((value).bits & ~(SIGN_BIT | QNAN)))

And see if that helps?

[minirop]

it worked, but I also had to modify wren_value.h:L667, change 64 to 32.:

return (Value)(SIGN_BIT | QNAN | (uint32_t)(obj));

on another (not serious) point, I also hade to remove -fPIC since « all code is position independent ».

[lluchs]

FWIW removing -Werror also makes it compile just fine (passes all tests).

[munificent]

I may still need to do a fix here, but I just landed a bunch of patches to make Wren compile as C++. That involves changing the value representation, so this might be fixed. Or, who knows, made worse.

Any chance you could retest?

Thanks!

[minirop]

it does not compile with g++, I get src/main.c:183:3: sorry, unimplemented: non-trivial designated initializers not supported.

If had to make a few changes to to make it compile:
change the C++ standard to C++11 and change the initialization of "config" to:

WrenConfiguration config { // no equals sign
    reallocateFn: NULL, // field in the same order as the struct
    // Since we're running in a standalone process, be generous with memory.
    initialHeapSize: 1024 * 1024 * 100,
    minHeapSize: 0,
    heapGrowthPercent: 0
  };

Also I know how to fix what causes the segfault of my first post, but I have no idea why. Just print the value of pinned in wrapPinObj:

void wrenPinObj(WrenVM* vm, Obj* obj, WrenPinnedObj* pinned)
{
  printf("%p\n", pinned); // <-- remove this line and it will segfault
  pinned->obj = obj;
  pinned->previous = vm->pinned;
  vm->pinned = pinned;
}

[munificent]

I'd like to not require C++11 (although, of course, it should allow that). I just went ahead and removed that initializer and initialized the struct manually. Does that help?

[minirop]

it does to compile in C++98 now.
About the casting in AS_OBJ and wrenObjectToValue, maybe using uintptr_t could help.

[munificent]

it does to compile in C++98 now.

\o/

About the casting in AS_OBJ and wrenObjectToValue, maybe using uintptr_t could help.

Maybe, I think just truncating works too. I'll try to get a fix in soon for that.

[minirop]

uintptr_t would help because it should equivalent to uint32_t on x86 and to uint64_t on x86_64. No need to another #if/#else to avoid the cast [...] of different size.

ps: I read the standard and it says that uintptr_t is optional, but so is uintN_t.

[munificent]

OK, I think I got it. If not, let me know.

[minirop]

compiled perfectly (C & C++) \o/

[munificent]

🎉