Update doc for 6.1 release

Author: finagolfin

README.md

@@ -9,8 +9,8 @@ emulator](https://github.com/finagolfin/swift-android-sdk/blob/main/.github/work
 
 ## Cross-compiling and testing Swift packages with the Android SDK bundle
 
-To build with the Swift 6 SDK bundle, first download [the official open-source
-Swift 6.0.3 toolchain for linux or macOS](https://swift.org/install)
+To build with the Swift 6.1 SDK bundle, first download [the official open-source
+Swift 6.1 toolchain for linux or macOS](https://swift.org/install)
 (make sure to install the Swift dependencies linked there). Install the OSS
 toolchain on macOS as detailed in [the instructions for using the static linux
 Musl SDK bundle at swift.org](https://www.swift.org/documentation/articles/static-linux-getting-started.html).
@@ -19,15 +19,15 @@ On linux, simply download the toolchain, unpack it, and add it to your `PATH`.
 Next, install the Android SDK bundle by having the Swift toolchain directly
 download it:
 ```
-swift sdk install https://github.com/finagolfin/swift-android-sdk/releases/download/6.0.3/swift-6.0.3-RELEASE-android-24-0.1.artifactbundle.tar.gz --checksum 4566f23ae2d36dc5c02e915cd67d83b2af971faca4b2595fdd75cf0286acfac1
+swift sdk install https://github.com/finagolfin/swift-android-sdk/releases/download/6.1/swift-6.1-RELEASE-android-24-0.1.artifactbundle.tar.gz --checksum 971f3b1fd03c059803d625f0a412d7e8c4c6f34440f5216ceaf13e886e8e706f
 ```
 or alternately, download the SDK bundle with your favorite downloader and install
 it separately:
 ```
-> wget https://github.com/finagolfin/swift-android-sdk/releases/download/6.0.3/swift-6.0.3-RELEASE-android-24-0.1.artifactbundle.tar.gz
-> sha256sum swift-6.0.3-RELEASE-android-24-0.1.artifactbundle.tar.gz
-4566f23ae2d36dc5c02e915cd67d83b2af971faca4b2595fdd75cf0286acfac1 swift-6.0.3-RELEASE-android-24-0.1.artifactbundle.tar.gz
-> swift sdk install swift-6.0.3-RELEASE-android-24-0.1.artifactbundle.tar.gz
+> wget https://github.com/finagolfin/swift-android-sdk/releases/download/6.1/swift-6.1-RELEASE-android-24-0.1.artifactbundle.tar.gz
+> sha256sum swift-6.1-RELEASE-android-24-0.1.artifactbundle.tar.gz
+971f3b1fd03c059803d625f0a412d7e8c4c6f34440f5216ceaf13e886e8e706f swift-6.1-RELEASE-android-24-0.1.artifactbundle.tar.gz
+> swift sdk install swift-6.1-RELEASE-android-24-0.1.artifactbundle.tar.gz
 ```
 You can check if it was properly installed by running `swift sdk list`.
 
@@ -56,20 +56,20 @@ one depends on the example executables `color`, `generate-manual`, `math`,
 point at test data in the repo: I've had success moving this data with the test
 runner, after modifying the test source so it has the path to this test data in
 the Android test environment. See the example of [swift-crypto on the
-CI](https://github.com/finagolfin/swift-android-sdk/blob/6.0.3/.github/workflows/sdks.yml#L506).
+CI](https://github.com/finagolfin/swift-android-sdk/blob/6.1/.github/workflows/sdks.yml#L516).
 
 You can copy these executables and the Swift runtime libraries to [an emulator
-or a USB debugging-enabled device with adb](https://github.com/swiftlang/swift/blob/release/6.0/docs/Android.md#3-deploying-the-build-products-to-the-device),
+or a USB debugging-enabled device with adb](https://github.com/swiftlang/swift/blob/release/6.1/docs/Android.md#3-deploying-the-build-products-to-the-device),
 or put them on an Android device with [a terminal emulator app like Termux](https://termux.dev/en/).
 I test aarch64 with Termux so I'll show how to run the test runner there, but
-the process is similar with adb, [as can be seen on the CI](https://github.com/finagolfin/swift-android-sdk/blob/6.0.3/.github/workflows/sdks.yml#L454).
+the process is similar with adb, [as can be seen on the CI](https://github.com/finagolfin/swift-android-sdk/blob/6.1/.github/workflows/sdks.yml#L462).
 
-Copy the test executables to the same directory as the Swift 6 runtime libraries:
+Copy the test executables to the same directory as the Swift 6.1 runtime libraries:
 ```
 cp .build/aarch64-unknown-linux-android24/debug/{swift-argument-parserPackageTests.xctest,color,generate-manual,math,repeat,roll} ..
-cp ~/.swiftpm/swift-sdks/swift-6.0.3-RELEASE-android-24-0.1.artifactbundle/swift-6.0.3-release-android-24-sdk/android-27c-sysroot/usr/lib/aarch64-linux-android/lib*.so ..
+cp ~/.swiftpm/swift-sdks/swift-6.1-RELEASE-android-24-0.1.artifactbundle/swift-6.1-release-android-24-sdk/android-27c-sysroot/usr/lib/aarch64-linux-android/lib*.so ..
 ```
-You can copy the test executables and Swift 6 runtime libraries to Termux using
+You can copy the test executables and Swift 6.1 runtime libraries to Termux using
 scp from OpenSSH, run these commands in Termux on the Android device:
 ```
 uname -m # check if you're running on the right architecture, should say `aarch64`
@@ -83,9 +83,8 @@ scp [email protected]:{swift-argument-parserPackageTests.xctest,color,generat
 ```
 I've tried several Swift packages, including some mostly written in C or C++,
 and all the cross-compiled tests passed. Note that while this SDK bundle is
-compiled against Android API 24, there was a regression in Swift 6 so that
-Foundation can only be run on Android API 29 or later, finagolfin/swift-android-sdk#175.
-I will update the SDK bundle when I find a fix for that new issue.
+compiled against Android API 24, you can also specify an arbitrary later API to
+compile against, eg `--swift-sdk aarch64-unknown-linux-android29`.
 
 You can even run armv7 tests on an aarch64 device, though Termux may require
 running `unset LD_PRELOAD` before invoking an armv7 test runner on aarch64.
@@ -108,7 +107,7 @@ refer to any FILE pointers like this](https://github.com/swiftlang/swift-tools-s
 #if canImport(Android)
 typealias FILEPointer = OpaquePointer
 ```
-Those changes are all I had to do [to port swift-argument-parser to
+Those changes are all I had to make [to port swift-argument-parser to
 Android](https://github.com/apple/swift-argument-parser/pull/651/files).
 
 ## Building an Android app with Swift
@@ -127,32 +126,32 @@ packagingOptions {
 
 ## Building an Android SDK from source
 
-Download the Swift 6.0.3 compiler as above and Android NDK 27c (only building
+Download the Swift 6.1 compiler as above and Android NDK 27c (only building
 the Android SDKs on linux works for now). Check out this repo and run
-`SWIFT_TAG=swift-6.0.3-RELEASE ANDROID_ARCH=aarch64 swift get-packages-and-swift-source.swift`
+`SWIFT_TAG=swift-6.1-RELEASE ANDROID_ARCH=aarch64 swift get-packages-and-swift-source.swift`
 to get some prebuilt Android libraries and the Swift source to build an AArch64
-SDK. If you pass in a different tag like `swift-DEVELOPMENT-SNAPSHOT-2025-01-05-a`
+SDK. If you pass in a different tag like `swift-DEVELOPMENT-SNAPSHOT-2025-04-03-a`
 for the latest Swift trunk snapshot and pass in the path to the corresponding
 prebuilt Swift toolchain to `build-script` below, you can build a Swift trunk
 SDK too, as seen on the CI.
 
 Next, apply two patches from this repo to the Swift source, which make
 modifications for NDK 27 and [the Foundation rewrite in Swift 6 that was merged
-this summer](https://www.swift.org/blog/foundation-preview-now-available/), and
+last summer](https://www.swift.org/blog/foundation-preview-now-available/), and
 substitute a string for NDK 27:
 ```
-git apply swift-android.patch swift-android-foundation-release.patch
+git apply swift-android.patch swift-android-testing-release.patch
 perl -pi -e 's%r26%r27%' swift/stdlib/cmake/modules/AddSwiftStdlib.cmake
 ```
 
-After making sure [needed build tools like python 3, CMake, and ninja](https://github.com/swiftlang/swift/blob/release/6.0/docs/HowToGuides/GettingStarted.md#linux)
+After making sure [needed build tools like python 3, CMake, and ninja](https://github.com/swiftlang/swift/blob/release/6.1/docs/HowToGuides/GettingStarted.md#linux)
 are installed, run the following `build-script` command with your local paths
 substituted instead:
 ```
 ./swift/utils/build-script -RA --skip-build-cmark --build-llvm=0 --android
 --android-ndk /home/finagolfin/android-ndk-r27c/ --android-arch aarch64 --android-api-level 24
---build-swift-tools=0 --native-swift-tools-path=/home/finagolfin/swift-6.0.3-RELEASE-ubuntu22.04/usr/bin/
---native-clang-tools-path=/home/finagolfin/swift-6.0.3-RELEASE-ubuntu22.04/usr/bin/
+--build-swift-tools=0 --native-swift-tools-path=/home/finagolfin/swift-6.1-RELEASE-ubuntu22.04/usr/bin/
+--native-clang-tools-path=/home/finagolfin/swift-6.1-RELEASE-ubuntu22.04/usr/bin/
 --host-cc=/usr/bin/clang-13 --host-cxx=/usr/bin/clang++-13
 --cross-compile-hosts=android-aarch64 --cross-compile-deps-path=/home/finagolfin/swift-release-android-aarch64-24-sdk
 --skip-local-build --xctest --swift-install-components='clang-resource-dir-symlink;license;stdlib;sdk-overlay'
@@ -178,11 +177,11 @@ Here is a description of what the above Swift script is doing:
 This prebuilt SDK was compiled against Android API 24, because the Swift
 Foundation libraries require some libraries like libcurl, that are pulled from the
 prebuilt library packages used by the Termux app, which are built against Android
-API 24. Specifically, it downloads the libandroid-spawn, libcurl, and libxml2
-packages and their handful of dependencies from the [Termux package
-repository](https://packages.termux.dev/apt/termux-main/pool/main/).
+API 24. Specifically, it downloads the libandroid-execinfo, libandroid-spawn,
+libcurl, and libxml2 packages and their handful of dependencies from the [Termux
+package repository](https://packages.termux.dev/apt/termux-main/pool/main/).
 
-Each one is unpacked with `ar x libcurl_8.10.1-1_aarch64.deb; tar xf data.tar.xz` and
+Each one is unpacked with `ar x libcurl_8.13.0_aarch64.deb; tar xf data.tar.xz` and
 the resulting files moved to a newly-created Swift release SDK directory:
 ```
 mkdir swift-release-android-aarch64-24-sdk
@@ -200,8 +199,8 @@ patchelf --set-rpath \$ORIGIN libandroid-spawn.so libcurl.so libxml2.so
 
 # repeat the following for all versioned Termux libraries, as needed
 rm libxml2.so libxml2.so.2
-readelf -d libxml2.so.2.13.4
-mv libxml2.so.2.13.4 libxml2.so
+readelf -d libxml2.so.2.13.7
+mv libxml2.so.2.13.7 libxml2.so
 patchelf --set-soname libxml2.so libxml2.so
 patchelf --replace-needed libz.so.1 libz.so libxml2.so
 ```
@@ -215,9 +214,9 @@ packages, by compiling against a more recent Android API that doesn't need the
 `libandroid-spawn` backport, and by cross-compiling libcurl/libxml2 and their
 dependencies yourself or not using FoundationNetworking and FoundationXML.
 
-Finally, it gets [the 6.0.3 source](https://github.com/swiftlang/swift/releases/tag/swift-6.0.3-RELEASE)
-tarballs for ten Swift repos and renames them to `llvm-project/`, `swift/`,
+Finally, it gets [the 6.1 source](https://github.com/swiftlang/swift/releases/tag/swift-6.1-RELEASE)
+tarballs for eleven Swift repos and renames them to `llvm-project/`, `swift/`,
 `swift-syntax`, `swift-experimental-string-processing`, `swift-corelibs-libdispatch`,
 `swift-corelibs-foundation`, `swift-collections`, `swift-foundation`,
-`swift-foundation-icu`, and `swift-corelibs-xctest`, as required by the Swift
-`build-script`.
+`swift-foundation-icu`, `swift-corelibs-xctest`, and `swift-testing`, as required
+by the Swift `build-script`.