error: use of unresolved identifier 'DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2'

[dropbear32]

I'm getting this error after running the following commands:

cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release . -D CMAKE_Swift_FLAGS="-sdk %SDK% -I %SDK%/usr/lib/swift -L %SDK%/usr/lib/swift/%OS%"
ninja -C build SwiftWin32 HelloSwift

I've run curl -sL "https://raw.githubusercontent.com/apple/swift/master/stdlib/public/Platform/winsdk.modulemap" -o "%UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap" in an administrator Developer prompt and it made no difference.

Is there a different/newer/older modulemap I need to clone?

[compnerd]

Bleh, this is a compatibility issue. DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2 doesn't get pulled in correctly from the clang importer. We should provide a definition for it in WinSDK+Extensions.swift for compatibility. Thanks for the report!

[compnerd]

@atirit would you mind testing #26? (CI currently is setup for 5.3)

[dropbear32]

Sure! I'll do my best.

[dropbear32]

I would get this by going through the Windows.md guide again, right?

[compnerd]

@atirit no, that is far overkill. I would say just apply the change (#26) to your repository and just build swift-win32.

[dropbear32]

Gotcha.

[dropbear32]

Adding the following to Application.swift:

#if swift(>=5.3)
#else
// windef.h
internal let DPI_AWARENESS_CONTEXT_UNAWARE: DPI_AWARENESS_CONTEXT =
    DPI_AWARENESS_CONTEXT(bitPattern: -1)!
internal let DPI_AWARENESS_CONTEXT_SYSTEM_AWARE: DPI_AWARENESS_CONTEXT =
    DPI_AWARENESS_CONTEXT(bitPattern: -2)!
internal let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE: DPI_AWARENESS_CONTEXT =
    DPI_AWARENESS_CONTEXT(bitPattern: -3)!
internal let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2: DPI_AWARENESS_CONTEXT =
    DPI_AWARENESS_CONTEXT(bitPattern: -4)!
internal let DPI_AWARENESS_CONTEXT_UNAWARE_GDISCALED: DPI_AWARENESS_CONTEXT =
    DPI_AWARENESS_CONTEXT(bitPattern: -5)!
#endif

results in the following errors:

..\Sources\Application\Application.swift:33:45: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_UNAWARE: DPI_AWARENESS_CONTEXT =
                                            ^~~~~~~~~~~~~~~~~~~~~
..\Sources\Application\Application.swift:35:50: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_SYSTEM_AWARE: DPI_AWARENESS_CONTEXT =
                                                 ^~~~~~~~~~~~~~~~~~~~~
..\Sources\Application\Application.swift:37:55: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE: DPI_AWARENESS_CONTEXT =
                                                      ^~~~~~~~~~~~~~~~~~~~~
..\Sources\Application\Application.swift:39:58: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2: DPI_AWARENESS_CONTEXT =
                                                         ^~~~~~~~~~~~~~~~~~~~~
..\Sources\Application\Application.swift:41:55: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_UNAWARE_GDISCALED: DPI_AWARENESS_CONTEXT =
                                                      ^~~~~~~~~~~~~~~~~~~~~
..\Sources\Application\Application.swift:39:58: error: use of undeclared type 'DPI_AWARENESS_CONTEXT'
internal let DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2: DPI_AWARENESS_CONTEXT =
                                                         ^~~~~~~~~~~~~~~~~~~~~

Is there a different place I should be putting it? (Perhaps I misunderstood you and you meant the Swift repository, not the swift-win32 repository.)

[compnerd]

Nope, that is the right place, the error is interesting though. DPI_AWARENESS_CONTEXT comes from the modulemap in the WinSDK directory:

https://docs.microsoft.com/en-us/windows/win32/hidpi/dpi-awareness-context

IIRC, ShellScalingApi.h should include that header and provide the type definition. Can you verify that ShellCore is in %UniversalCRTSdkDir%\Include\%UCRTVersion%\um\module.modulemap?

That change allows for applications to actually scale properly for HiDPI (Retina in Apple parlance) displays.

[dropbear32]

I see the following in that file:

  module ShellCore {
    header "ShellScalingApi.h"
    export *

    link "shcore.lib"
  }

[compnerd]

Which version of the windows SDK are you using? (10.0.107763 or some other version?)

[dropbear32]

I believe I'm using version 10.0.17134.0. I have the following in C:\Program Files (x86)\Windows Kits\10\Include:

• 10.0.10240.0
• 10.0.16299.0
• 10.0.17134.0
• 10.0.17763.0
• 10.0.18362.0

I'm not quite sure how to determine the exact version I'm using.

[compnerd]

Ah, that is the problem! 10.0.17763.0 is the minimum required version for Windows. %UCRTVersion% in the environment should specify the version.

[dropbear32]

Running echo %UCRTVersion% returns 10.0.18362.0. Looks like I was wrong :P (I'm quite inept at Windows development if you couldn't tell already lol)