Index: clang/lib/CrossTU/CrossTranslationUnit.cpp
===================================================================
--- clang/lib/CrossTU/CrossTranslationUnit.cpp
+++ clang/lib/CrossTU/CrossTranslationUnit.cpp
@@ -668,8 +668,14 @@
   if (InvocationList)
     return llvm::Error::success();
 
+  SmallString<256> InvocationListFileAbsolutePath = CTUDir;
+  if (llvm::sys::path::is_absolute(InvocationListFilePath))
+    InvocationListFileAbsolutePath = InvocationListFilePath;
+  else
+    llvm::sys::path::append(InvocationListFileAbsolutePath,
+                            InvocationListFilePath);
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> FileContent =
-      llvm::MemoryBuffer::getFile(InvocationListFilePath);
+      llvm::MemoryBuffer::getFile(InvocationListFileAbsolutePath);
   if (!FileContent)
     return llvm::make_error<IndexError>(
         index_error_code::invocation_list_file_not_found);
Index: clang/test/Analysis/ctu-on-demand-parsing.c
===================================================================
--- clang/test/Analysis/ctu-on-demand-parsing.c
+++ clang/test/Analysis/ctu-on-demand-parsing.c
@@ -7,16 +7,16 @@
 // compile_commands.json is only needed for extdef_mapping, not for the analysis itself.
 // RUN: echo '[{"directory":"%t","command":"gcc -std=c89 -Wno-visibility ctu-other.c","file":"ctu-other.c"}]' | sed -e 's/\\/\\\\/g' > %t/compile_commands.json
 //
-// RUN: echo '"%t/ctu-other.c": ["gcc", "-std=c89", "-Wno-visibility", "ctu-other.c"]' | sed -e 's/\\/\\\\/g' > %t/invocations.yaml
+// RUN: echo '"%t/ctu-other.c": ["gcc", "-std=c89", "-Wno-visibility", "%t/ctu-other.c"]' | sed -e 's/\\/\\\\/g' > %t/invocations.yaml
 //
-// RUN: cd "%t" && %clang_extdef_map "%t/ctu-other.c" > externalDefMap.txt
+// RUN: %clang_extdef_map -p %t "%t/ctu-other.c" > %t/externalDefMap.txt
 //
-// RUN: cd "%t" && %clang_cc1 -fsyntax-only -std=c89 -analyze \
+// RUN: %clang_cc1 -fsyntax-only -std=c89 -analyze \
 // RUN:   -analyzer-checker=core,debug.ExprInspection \
 // RUN:   -analyzer-config experimental-enable-naive-ctu-analysis=true \
-// RUN:   -analyzer-config ctu-dir=. \
+// RUN:   -analyzer-config ctu-dir=%t \
 // RUN:   -analyzer-config ctu-invocation-list=invocations.yaml \
-// RUN:   -verify ctu-on-demand-parsing.c
+// RUN:   -verify %t/ctu-on-demand-parsing.c
 //
 // FIXME: Path handling should work on all platforms.
 // REQUIRES: system-linux
Index: clang/test/Analysis/ctu-on-demand-parsing.cpp
===================================================================
--- clang/test/Analysis/ctu-on-demand-parsing.cpp
+++ clang/test/Analysis/ctu-on-demand-parsing.cpp
@@ -11,20 +11,20 @@
 //
 // RUN: echo '{"%t/Inputs/ctu-chain.cpp": ["g++", "%t/Inputs/ctu-chain.cpp"], "%t/Inputs/ctu-other.cpp": ["g++", "%t/Inputs/ctu-other.cpp"]}' | sed -e 's/\\/\\\\/g' > %t/invocations.yaml
 //
-// RUN: cd "%t" && %clang_extdef_map Inputs/ctu-chain.cpp Inputs/ctu-other.cpp > externalDefMap.txt
+// RUN: %clang_extdef_map -p %t %t/Inputs/ctu-chain.cpp %t/Inputs/ctu-other.cpp > %t/externalDefMap.txt
 //
-// RUN: cd "%t" && %clang_analyze_cc1 \
+// RUN: %clang_analyze_cc1 \
 // RUN:   -analyzer-checker=core,debug.ExprInspection \
 // RUN:   -analyzer-config experimental-enable-naive-ctu-analysis=true \
-// RUN:   -analyzer-config ctu-dir=. \
+// RUN:   -analyzer-config ctu-dir=%t \
 // RUN:   -analyzer-config ctu-invocation-list=invocations.yaml \
-// RUN:   -verify ctu-on-demand-parsing.cpp
-// RUN: cd "%t" && %clang_analyze_cc1 \
+// RUN:   -verify %t/ctu-on-demand-parsing.cpp
+// RUN: %clang_analyze_cc1 \
 // RUN:   -analyzer-checker=core,debug.ExprInspection \
 // RUN:   -analyzer-config experimental-enable-naive-ctu-analysis=true \
-// RUN:   -analyzer-config ctu-dir=. \
+// RUN:   -analyzer-config ctu-dir=%t \
 // RUN:   -analyzer-config ctu-invocation-list=invocations.yaml \
-// RUN:   -analyzer-config display-ctu-progress=true ctu-on-demand-parsing.cpp 2>&1 | FileCheck %t/ctu-on-demand-parsing.cpp
+// RUN:   -analyzer-config display-ctu-progress=true %t/ctu-on-demand-parsing.cpp 2>&1 | FileCheck %t/ctu-on-demand-parsing.cpp
 //
 // CHECK: CTU loaded AST file: {{.*}}ctu-other.cpp
 // CHECK: CTU loaded AST file: {{.*}}ctu-chain.cpp