SwiftDriver: initial work to properly handle android cross-compilation #1560
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| if let sdk = parsedOptions.getLastArgument(.sdk)?.asSingle ?? env["SDKROOT"], !sdk.isEmpty { | ||
| rsrc = try VirtualPath(path: AbsolutePath(validating: sdk) | ||
| .appending(components: "usr", "lib", "swift") | ||
| .pathString) |
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Note that if -resource-dir is not specified, this behavior is already the default, so the only reason to do this is to override -resource-dir. Any reason why you need that? I think this is a bad idea to silently override it.
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This is not the default - this is going to try to prefer the resources in the SDK rather than the toolchain (which allows us to have platform specific resources).
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Huh, never mind, what I'm saying was true of the old C++ Driver, but is not true of this new swift-driver, after manually testing it on linux.
I think this is a genuine discrepancy between the two drivers that we should find the root cause and fix, rather than putting in partial workarounds like this.
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With this set of changes I am down to: The bits that I would like to remove: This feels like we are failing to setup the library search path when we have a This is due to my builds missing clang_rt.builtins-... for Android and so we need to pull some files from the NDK. Addressing those two issues would give us the following invocation: and with |
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The reason this entire approach doesn't already work is because of a regression in this new Swift Driver, see #1562. We should fix that for all platforms, not paper over it with these Android-specific changes. |
The intent here is to permit the Windows/macOS style cross-compilation for Android. This involves passing `-sdk` with the path to the "Swift SDK" which overlays the system's native SDK (NDK). The `ANDROID_NDK_ROOT` is a well-defined environment variable (setup by the SDK installer as well as a general expectation for Android development) that identifies the root of the installation of the NDK. This allows us to locate the native SDK root (`--sysroot`) for driving the linker driver amongst other paths.
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I'm not sure I'm following the "papering over" here. The idea here is to default the |
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There are two aspects to this pull, having this new swift driver read environment variables like I don't think we should hard-code such environment variables in this driver, but always "explicitly specify" them, as you say. As for finding build files, the reason that doesn't work already is #1562: take a look at my detailed writeup from a couple weeks ago for why. |
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I disagree with you on that point. I would like the default value behavior for the targets where possible, much as it works on macOS. Fixing the behavior to work with the parameters however should be done. |
The intent here is to permit the Windows/macOS style cross-compilation for Android. This involves passing
-sdkwith the path to the "Swift SDK" which overlays the system's native SDK (NDK). TheANDROID_NDK_ROOTis a well-defined environment variable (setup by the SDK installer as well as a general expectation for Android development) that identifies the root of the installation of the NDK. This allows us to locate the native SDK root (--sysroot) for driving the linker driver amongst other paths.