llvm/0004-devtoolset.patch

--- a/tools/clang/lib/Driver/ToolChains.cpp
+++ b/tools/clang/lib/Driver/ToolChains.cpp
@@ -1062,6 +1062,18 @@
     // And finally in /usr.
     if (D.SysRoot.empty())
       Prefixes.push_back("/usr");
+
+    // RedHat Developer Toolset support
+    if (const char *software_collections = getenv("X_SCLS")) {
+      SmallVector<StringRef, 4> Scls;
+      StringRef(software_collections).split(Scls, StringRef(" "), -1, false);
+      for (const auto &Scl : Scls) {
+        if (!Scl.startswith(StringRef("devtoolset-")))
+          continue;
+        const std::string SclPath = std::string("/opt/rh/") + Scl.str() + std::string("/root/usr");
+        Prefixes.push_back(SclPath);
+      }
+    }
   }
 
   // Loop over the various components which exist and select the best GCC