diff --git a/packages/compiler-cli/src/ngtsc/util/src/typescript.ts b/packages/compiler-cli/src/ngtsc/util/src/typescript.ts
index dc38c2a96c..c4632994b9 100644
--- a/packages/compiler-cli/src/ngtsc/util/src/typescript.ts
+++ b/packages/compiler-cli/src/ngtsc/util/src/typescript.ts
@@ -105,7 +105,7 @@ export function getRootDirs(host: ts.CompilerHost, options: ts.CompilerOptions):
   // See:
   // https://github.com/Microsoft/TypeScript/blob/3f7357d37f66c842d70d835bc925ec2a873ecfec/src/compiler/sys.ts#L650
   // Also compiler options might be set via an API which doesn't normalize paths
-  return rootDirs.map(rootDir => absoluteFrom(rootDir));
+  return rootDirs.map(rootDir => absoluteFrom(host.getCanonicalFileName(rootDir)));
 }
 
 export function nodeDebugInfo(node: ts.Node): string {