Strip Android version when looking up toolchain paths.

Summary:
Android target triples can include a version number in the abi field
(e.g. 'aarch64-linux-android21'), used for checking for availability.
However, the driver was searching for toolchain binaries using the
passed in triple as a prefix.

Reviewers: srhines, danalbert, t.p.northover

Subscribers: t.p.northover, aemerson, tberghammer, danalbert, srhines, cfe-commits

Differential Revision: http://reviews.llvm.org/D21163

llvm-svn: 272413
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index f7e1530..7db9e11 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -2343,7 +2343,15 @@
     const char *Tool, const ToolChain &TC,
     SmallVectorImpl<std::string> &Names) const {
   // FIXME: Needs a better variable than DefaultTargetTriple
-  Names.emplace_back(DefaultTargetTriple + "-" + Tool);
+  StringRef Triple = DefaultTargetTriple;
+
+  // On Android, the target triple can include a version number that needs to
+  // be stripped.
+  if (TC.getTriple().isAndroid()) {
+    Triple = Triple.rtrim("0123456789");
+  }
+
+  Names.emplace_back((Triple + "-" + Tool).str());
   Names.emplace_back(Tool);
 
   // Allow the discovery of tools prefixed with LLVM's default target triple.