Strip .dll extension from raw-dylib link names

[Jake-Shadle]

As noted in the comment, currently windows-bindgen emits the full name of the dll including the extension, which will cause runtime failures since somewhere (linker? dynamic loader?) the extension is automatically added, causing the dll not to be found and abort.

I think the confusion may come from the RFC containing example code which does include the extension.

#[cfg(windows)]
#[link(name = "kernel32.dll", kind = "raw-dylib")]
#[allow(non_snake_case)]
extern "system" {
    fn GetStdHandle(nStdHandle: u32) -> *mut u8;
}

Note this doesn't impact bthprops.cpl which is the 1? case I could find of a dynamic lib having an extension other than .dll.

I was opening an issue and realized it was easier to just fix it.

[riverar]

Note this doesn't impact bthprops.cpl which is the 1? case I could find of a dynamic lib having an extension other than .dll.

There are plenty of other cases, see:

• DllImportAttribute dllName not explicitly specified for bthprops.cpl win32metadata#714
• Bug: Application is linked to winspool.dll instead of winspool.drv #1447
• All DllImport attributes should have fully qualified library name win32metadata#1021
• etc.

It's not optimal or really possible to guess the correct answer so we make it explicit in metadata.

Do you have a repro that demonstrates a failure? If so, please open an issue. Be aware raw-dylib is in use by rustc today.

[ChrisDenton]

I think the issue here is that it needs the +verbatim modifier.

#[cfg(windows)]
-#[link(name = "kernel32.dll", kind = "raw-dylib")]
+#[link(name = "kernel32.dll", kind = "raw-dylib", modifiers = "+verbatim")]
#[allow(non_snake_case)]
extern "system" {
    fn GetStdHandle(nStdHandle: u32) -> *mut u8;
}

[kennykerr]

This is a complicated issue, but it has been discussed at length here:

rust-lang/rust#58713

The windows-targets crate support for raw-dylib can be found here:

https://github.com/microsoft/windows-rs/blob/master/crates/libs/targets/src/lib.rs

And it is tested here:

https://github.com/microsoft/windows-rs/blob/master/.github/workflows/raw_dylib.yml