Android: fix ABI triple detection, disable C++ modules flags, and

bring over tweaks from old bootstrap script to new one.

Author: finagolfin

Sources/Build/BuildPlan.swift

@@ -226,13 +226,13 @@ public final class ClangTargetBuildDescription {
             args += buildParameters.indexStoreArguments(for: target)
         }
 
-        if !buildParameters.triple.isWindows() {
-            // Using modules currently conflicts with the Windows SDKs.
+        if !buildParameters.triple.isWindows() && !buildParameters.triple.isAndroid() {
+            // Using modules currently conflicts with the Windows and Android SDKs.
             args += ["-fmodules", "-fmodule-name=" + target.c99name]
         }
         args += ["-I", clangTarget.includeDir.pathString]
         args += additionalFlags
-        if !buildParameters.triple.isWindows() {
+        if !buildParameters.triple.isWindows() && !buildParameters.triple.isAndroid() {
             args += moduleCacheArgs
         }
         args += buildParameters.sanitizers.compileCFlags()

Sources/Build/Triple.swift

@@ -61,7 +61,7 @@ public struct Triple: Encodable {
 
     public enum ABI: String, Encodable {
         case unknown
-        case android = "androideabi"
+        case android
     }
 
     public init(_ string: String) throws {
@@ -81,8 +81,7 @@ public struct Triple: Encodable {
             throw Error.unknownOS
         }
 
-        let abiString = components.count > 3 ? components[3] : nil
-        let abi = abiString.flatMap(ABI.init)
+        let abi = components.count > 3 ? Triple.parseABI(components[3]) : nil
 
         self.tripleString = string
         self.arch = arch
@@ -101,6 +100,13 @@ public struct Triple: Encodable {
         return nil
     }
 
+    fileprivate static func parseABI(_ string: String) -> ABI? {
+        if string.hasPrefix(ABI.android.rawValue) {
+            return ABI.android
+        }
+        return nil
+    }
+
     public func isAndroid() -> Bool {
         return os == .linux && abi == .android
     }

Sources/TSCBasic/CMakeLists.txt

@@ -62,3 +62,8 @@ install(TARGETS TSCBasic
   LIBRARY DESTINATION lib
   RUNTIME DESTINATION bin)
 endif()
+
+# Don't use GNU strerror_r on Android.
+if(CMAKE_SYSTEM_NAME STREQUAL Android)
+  target_compile_options(TSCBasic PUBLIC "SHELL:-Xcc -U_GNU_SOURCE")
+endif()

Utilities/bootstrap

@@ -232,7 +232,14 @@ def get_build_target(args):
     if platform.system() == 'Darwin':
         return "x86_64-apple-macosx"
     elif platform.system() == 'Linux':
-        if platform.machine() == 'x86_64':
+        if 'ANDROID_DATA' in os.environ:
+            if platform.machine().startswith('armv7'):
+                return 'armv7a-unknown-linux-androideabi'
+            elif platform.machine() == 'aarch64':
+                return 'aarch64-unknown-linux-android'
+            else:
+                raise SystemExit("ERROR: unsupported Android platform:", platform.machine())
+        elif platform.machine() == 'x86_64':
             return "x86_64-unknown-linux-gnu"
         elif platform.machine() == "i686":
             return "i686-unknown-linux"
@@ -548,10 +555,15 @@ def get_swiftpm_flags(args):
             "-Xlinker", "@executable_path/../../../../../SharedFrameworks",
         ])
 
-    # Add a rpath to find core swift libraries on linux. We don't need a rpath
-    # for Darwin because the Swift libraries are present in the OS.
+    # Add a rpath to find core swift libraries on linux and Android. We don't
+    # need a rpath for Darwin because the Swift libraries are present in the OS.
     if platform.system() == 'Linux':
-        build_flags.extend(["-Xlinker", "-rpath=$ORIGIN/../lib/swift/linux"])
+        if 'ANDROID_DATA' in os.environ:
+            build_flags.extend(["-Xlinker", "-rpath=$ORIGIN/../lib/swift/android"])
+            # Don't use GNU strerror_r on Android.
+            build_flags.extend(["-Xswiftc", "-Xcc", "-Xswiftc", "-U_GNU_SOURCE"])
+        else:
+            build_flags.extend(["-Xlinker", "-rpath=$ORIGIN/../lib/swift/linux"])
 
     return build_flags