rustbuild/LLVM: Do not print installation messages for up-to-date files

src/bootstrap/native.rs

@@ -317,6 +317,10 @@ fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
 fn configure_cmake(builder: &Builder<'_>,
                    target: Interned<String>,
                    cfg: &mut cmake::Config) {
+    // Do not print installation messages for up-to-date files.
+    // LLVM and LLD builds can produce a lot of those and hit CI limits on log size.
+    cfg.define("CMAKE_INSTALL_MESSAGE", "LAZY");
+
     if builder.config.ninja {
         cfg.generator("Ninja");
     }