chore(profiling): improve SSI behavior and error messages for profiling

ddtrace/profiling/profiler.py

@@ -248,7 +248,10 @@ def _build_default_exporters(self):
 
                 return []
             except Exception as e:
-                LOG.error("Failed to initialize libdd collector (%s), falling back to the legacy collector", e)
+                try:
+                    LOG.error("Failed to load libdd (%s) (%s), falling back to legacy mode", e, ddup.failure_msg)
+                except Exception as ee:
+                    LOG.error("Failed to load libdd (%s) (%s), falling back to legacy mode", e, ee)
                 self._export_libdd_enabled = False
                 profiling_config.export.libdd_enabled = False
 
@@ -258,6 +261,12 @@ def _build_default_exporters(self):
                     self._stack_v2_enabled = False
                     profiling_config.stack.v2_enabled = False
 
+                # If this instance of ddtrace was injected, then do not enable profiling, since that will load
+                # protobuf, breaking some environments.
+                if profiling_config._injected:
+                    LOG.error("Profiling failures occurred in an injected instance of ddtrace, disabling profiling")
+                    return []
+
         # DEV: Import this only if needed to avoid importing protobuf
         # unnecessarily
         from ddtrace.profiling.exporter import http

releasenotes/notes/profiling-fix-autoinject-failure-48cc7d9a18cd70b9.yaml

@@ -0,0 +1,4 @@
+fixes:
+  - |
+    profiling: Improves the error message when the native exporter fails to load and stops profiling from starting
+    if ddtrace is also being injected.