don't optimize debuginfo for artifact dependencies

Author: lqd

src/cargo/ops/cargo_compile/mod.rs

@@ -1284,8 +1284,9 @@ fn traverse_and_share(
     let mut profile = unit.profile.clone();
 
     // If this is a build dependency, and it's not shared with runtime dependencies, we can weaken
-    // its debuginfo level to optimize build times.
-    if unit.kind.is_host() && profile.debuginfo.is_deferred() {
+    // its debuginfo level to optimize build times. We do nothing if it's an artifact dependency,
+    // as it and its debuginfo may end up embedded in the main program.
+    if unit.kind.is_host() && profile.debuginfo.is_deferred() && !unit.artifact.is_true() {
         // We create a "probe" test to see if a unit with the same explicit debuginfo level exists
         // in the graph. This is the level we'd expect if it was set manually or the default value
         // set by a profile for a runtime dependency: its canonical value.