diff --git a/pkgs/llvm-ompss2/default.nix b/pkgs/llvm-ompss2/default.nix
index dd0a426..90e5469 100644
--- a/pkgs/llvm-ompss2/default.nix
+++ b/pkgs/llvm-ompss2/default.nix
@@ -44,6 +44,9 @@ in wrapCCWith {
     echo "-L${gcc.cc}/lib/gcc/${targetConfig}/${gcc.version}" >> $out/nix-support/cc-ldflags
     echo "-L${gcc.cc.lib}/lib" >> $out/nix-support/cc-ldflags
 
+    for dir in ${gcc.cc}/lib/gcc/${targetConfig}/*/include; do
+      echo "-isystem $dir" >> $out/nix-support/cc-cflags
+    done
     for dir in ${gcc.cc}/include/c++/*; do
       echo "-isystem $dir" >> $out/nix-support/libcxx-cxxflags
     done