1Use the Nix include dirs and gcc runtime dir, when no sysroot is configured.
2
3--- a/lib/Driver/ToolChains/Linux.cpp
4+++ b/lib/Driver/ToolChains/Linux.cpp
5@@ -574,7 +574,7 @@
6
7 // Check for configure-time C include directories.
8 StringRef CIncludeDirs(C_INCLUDE_DIRS);
9- if (CIncludeDirs != "") {
10+ if (CIncludeDirs != "" && (SysRoot.empty() || SysRoot == "/")) {
11 SmallVector<StringRef, 5> dirs;
12 CIncludeDirs.split(dirs, ":");
13 for (StringRef dir : dirs) {