diff --git a/src/bootstrap/ci-llvm-libstdcpp-version-threshold b/src/bootstrap/ci-llvm-libstdcpp-version-threshold
new file mode 100644
index 0000000000000..ae9a76b9249ad
--- /dev/null
+++ b/src/bootstrap/ci-llvm-libstdcpp-version-threshold
@@ -0,0 +1 @@
+8.0.0
diff --git a/src/bootstrap/src/core/sanity.rs b/src/bootstrap/src/core/sanity.rs
index 9c3df6fa9e39b..8132776fdd9e5 100644
--- a/src/bootstrap/src/core/sanity.rs
+++ b/src/bootstrap/src/core/sanity.rs
@@ -99,6 +99,22 @@ pub fn check(build: &mut Build) {
         cmd_finder.must_have("git");
     }
 
+    if !build.config.dry_run() && build.config.llvm_from_ci {
+        let cxx = build.cxx(build.build).unwrap();
+        let mut cxx_cmd = Command::new(cxx);
+        cxx_cmd.arg("-dumpversion");
+
+        let current_libstdcpp_v = semver::Version::parse(output(&mut cxx_cmd).trim()).unwrap();
+        let libstdcpp_v_threshold = semver::Version::parse(include_str!("../../ci-llvm-libstdcpp-version-threshold")).unwrap();
+
+        if current_libstdcpp_v.lt(&libstdcpp_v_threshold) {
+            eprintln!("\nCurrent libstdc++ version is '{current_libstdcpp_v}', which is too old and below the required threshold of '{libstdcpp_v_threshold}'.");
+            // In case the user has a custom setup that includes a recent libstdc++ with an old c++ compiler, this information might be useful to them.
+            eprintln!("If you think this is a mistake, you can bypass this sanity check by setting 'BOOTSTRAP_SKIP_TARGET_SANITY' env variable to '1'.");
+            crate::exit!(1);
+        }
+    }
+
     // We need cmake, but only if we're actually building LLVM or sanitizers.
     let building_llvm = build
         .hosts