The source-map flattening was throwing an error when there is a cyclic dependency between source files and source-maps. The error was either a custom one describing the cycle, or a "Maximum call stack size exceeded" one. Now this is handled more leniently, resulting in a partially loaded source file (or source-map) and a warning logged. Fixes #35727 Fixes #35757 Fixes https://github.com/angular/angular-cli/issues/17106 Fixes https://github.com/angular/angular-cli/issues/17115 PR Close #36452