diff --git a/Sources/System/FilePath/FilePathParsing.swift b/Sources/System/FilePath/FilePathParsing.swift
index f372dd67..efff3492 100644
--- a/Sources/System/FilePath/FilePathParsing.swift
+++ b/Sources/System/FilePath/FilePathParsing.swift
@@ -168,7 +168,7 @@ extension FilePath {
             readIdx = nextStart
             continue
           }
-          assert(self.root == nil && self.components.first!.kind == .parentDirectory)
+          assert(!hasRoot && _isParentDirectory(priorComponent))
         }
       }
 
diff --git a/Tests/SystemTests/FilePathTests/FilePathSyntaxTest.swift b/Tests/SystemTests/FilePathTests/FilePathSyntaxTest.swift
index 0fdfbc27..9df2019e 100644
--- a/Tests/SystemTests/FilePathTests/FilePathSyntaxTest.swift
+++ b/Tests/SystemTests/FilePathTests/FilePathSyntaxTest.swift
@@ -436,6 +436,13 @@ final class FilePathSyntaxTest: XCTestCase {
         lexicallyNormalized: ".."
       ),
 
+      .unix(
+        "foo/../../../bar",
+        dirname: "foo/../../..", basename: "bar",
+        components: ["foo", "..", "..", "..", "bar"],
+        lexicallyNormalized: "../../bar"
+      ),
+
       .unix(
         "a/.././.././../b",
         dirname: "a/.././.././..", basename: "b",