Index: cfe/trunk/lib/Driver/ToolChains/Gnu.cpp
===================================================================
--- cfe/trunk/lib/Driver/ToolChains/Gnu.cpp
+++ cfe/trunk/lib/Driver/ToolChains/Gnu.cpp
@@ -1788,17 +1788,14 @@
   }
 
   // Non-Solaris is much simpler - most systems just go with "/usr".
-  if (SysRoot.empty()) {
-    // Yet, still look for RHEL devtoolsets
-    // (should it be done Linux-only??)
+  if (SysRoot.empty() && TargetTriple.getOS() == llvm::Triple::Linux) {
+    // Yet, still look for RHEL devtoolsets.
     Prefixes.push_back("/opt/rh/devtoolset-6/root/usr");
     Prefixes.push_back("/opt/rh/devtoolset-4/root/usr");
     Prefixes.push_back("/opt/rh/devtoolset-3/root/usr");
     Prefixes.push_back("/opt/rh/devtoolset-2/root/usr");
-    Prefixes.push_back("/usr");
-  } else {
-    Prefixes.push_back(SysRoot.str() + "/usr");
   }
+  Prefixes.push_back(SysRoot.str() + "/usr");
 }
 
 /*static*/ void Generic_GCC::GCCInstallationDetector::CollectLibDirsAndTriples(