[Driver] Obey computed sysroot when finding libc++ headers.

Summary:
A handful of targets will try some default paths if --sysroot is not provided.
If that is the case, it should be used for the libc++ header paths.

Reviewers: srhines, EricWF

Reviewed By: srhines

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D45292

llvm-svn: 331389

diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
index e584fcd..5dca5ff 100644 (file)
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -793,13 +793,14 @@ static std::string DetectLibcxxIncludePath(StringRef base) {
 
 void Linux::addLibCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
                                   llvm::opt::ArgStringList &CC1Args) const {
+  const std::string& SysRoot = computeSysRoot();
   const std::string LibCXXIncludePathCandidates[] = {
       DetectLibcxxIncludePath(getDriver().Dir + "/../include/c++"),
       // If this is a development, non-installed, clang, libcxx will
       // not be found at ../include/c++ but it likely to be found at
       // one of the following two locations:
-      DetectLibcxxIncludePath(getDriver().SysRoot + "/usr/local/include/c++"),
-      DetectLibcxxIncludePath(getDriver().SysRoot + "/usr/include/c++") };
+      DetectLibcxxIncludePath(SysRoot + "/usr/local/include/c++"),
+      DetectLibcxxIncludePath(SysRoot + "/usr/include/c++") };
   for (const auto &IncludePath : LibCXXIncludePathCandidates) {
     if (IncludePath.empty() || !getVFS().exists(IncludePath))
       continue;