Code loading: do the "skipping mtime check for stdlib" check in both …

…branches on the value of `ispath(f)`

base/loading.jl

@@ -3117,7 +3117,15 @@ end
             end
             for chi in includes
                 f, ftime_req = chi.filename, chi.mtime
-                if !ispath(f)
+                if ispath(f)
+                    # `ispath(f)` is true
+                    if isfile(f) && startswith(f, Sys.STDLIB)
+                        # mtime is changed by extraction
+                        @debug "Skipping mtime check for file $f used by $cachefile, since it is a stdlib"
+                        continue
+                    end
+                else
+                    # `ispath(f)` is false
                     _f = fixup_stdlib_path(f)
                     if isfile(_f) && startswith(_f, Sys.STDLIB)
                         # mtime is changed by extraction