diff --git a/clang/test/Tooling/clang-check-fixit.cpp b/clang/test/Tooling/clang-check-fixit.cpp
deleted file mode 100644
index 6b03334f72cd2..0000000000000
--- a/clang/test/Tooling/clang-check-fixit.cpp
+++ /dev/null
@@ -1,25 +0,0 @@
-// RUN: rm -rf %t
-// RUN: mkdir %t
-//
-// RUN: sed -s 's,^//.*,//,' %s > %t/absolute-fixed.cpp
-// RUN: sed -s 's,^//.*,//,' %s > %t/absolute-json.cpp
-// RUN: sed -s 's,^//.*,//,' %s > %t/relative-fixed.cpp
-// RUN: sed -s 's,^//.*,//,' %s > %t/relative-json.cpp
-//
-// RUN: clang-check %t/absolute-fixed.cpp -fixit -- 2>&1 | FileCheck %s
-//
-// RUN: echo '[{ "directory": "%t", \
-// RUN:   "command": "/path/to/clang -c %t/absolute-json.cpp", \
-// RUN:   "file": "%t/absolute-json.cpp" }]' > %t/compile_commands.json
-// RUN: clang-check %t/absolute-json.cpp -fixit 2>&1 | FileCheck %s
-//
-// RUN: cd %t
-// RUN: clang-check relative-fixed.cpp -fixit -- 2>&1 | FileCheck %s
-//
-// RUN: echo '[{ "directory": "%t", \
-// RUN:   "command": "/path/to/clang -c relative-json.cpp", \
-// RUN:   "file": "relative-json.cpp" }]' > %t/compile_commands.json
-// RUN: clang-check relative-json.cpp -fixit 2>&1 | FileCheck %s
-typedef int T
-// CHECK: .cpp:[[@LINE-1]]:14: error: expected ';' after top level declarator
-// CHECK: .cpp:[[@LINE-2]]:14: note: FIX-IT applied suggested code changes
diff --git a/clang/tools/clang-check/ClangCheck.cpp b/clang/tools/clang-check/ClangCheck.cpp
index ce400b5c20005..96a593a29b46f 100644
--- a/clang/tools/clang-check/ClangCheck.cpp
+++ b/clang/tools/clang-check/ClangCheck.cpp
@@ -90,6 +90,9 @@ class FixItOptions : public clang::FixItOptions {
   }
 
   std::string RewriteFilename(const std::string& filename, int &fd) override {
+    assert(llvm::sys::path::is_absolute(filename) &&
+           "clang-fixit expects absolute paths only.");
+
     // We don't need to do permission checking here since clang will diagnose
     // any I/O errors itself.