C# PInvoke returning invalid/wrong bool value, only when native code compiled in debug mode (OSX only)

Question

So, I have a weird issue. I am doing a simple PInvoke call to get a boolean from managed code.

C/C++

Q_DECL_EXPORT bool net_variant_getBool(NetVariantContainer* container)
{
    bool result = container->variant->getBool();

    // This function will only return the right value if I use the following code in OSX in release mode (debug works with or without it).
    // qDebug("Return value is: %d", result);

    return result;
}

C#

[DllImport("QmlNet.dylib")]
static extern bool net_variant_getBool(IntPtr variant);

The code above, as is, works perfectly on Linux/Windows in either debug or release mode, and OSX in debug mode only.

On OSX in release mode, the resulting value in C# is wrong. If I attempt to log what the returning bool is (to figure out the issue), it prints out the right value, and then the right value is returned! That's right, the qDebug macro above that is commented out will fix my issue if compiled in. Wth?

This problem only presents it's self in Release mode on OSX/clang.

Here is the compilation output on OSX for both debug and release builds. https://gist.github.com/pauldotknopf/3949b7e86d6a4bfb59788dd0b7c44536

I'm utterly lost. Anybody have any ideas? I don't want to ship debug libs!

Does this answer your question? C# DllImport with C++ boolean function not returning correctly — malat
– malat, Commented Jan 16, 2024 at 9:42

Paul Knopf · Accepted Answer · 2018-12-25 19:54:50Z

1

It turns out that bool is a non-blittable type and can't be used as a return value. See here.

I changed my code to return a byte instead.

answered Dec 25, 2018 at 19:54

Paul Knopf

9,80424 gold badges83 silver badges158 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

malat Over a year ago

[MarshalAs(UnmanagedType.I1)] see stackoverflow.com/questions/4608876/…

Collectives™ on Stack Overflow

C# PInvoke returning invalid/wrong bool value, only when native code compiled in debug mode (OSX only)

1 Answer 1

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related