Index: openmp/README.rst
===================================================================
--- openmp/README.rst
+++ openmp/README.rst
@@ -130,6 +130,10 @@
   Specify full path to ``FileCheck`` executable for running tests.  The default
   is to search the ``PATH`` and the directory in **OPENMP_LLVM_TOOLS_DIR**.
 
+**OPENMP_NOT_EXECUTABLE** = ``/path/to/not``
+  Specify full path to ``not`` executable for running tests.  The default
+  is to search the ``PATH`` and the directory in **OPENMP_LLVM_TOOLS_DIR**.
+
 Options for ``libomp``
 ----------------------
 
Index: openmp/cmake/OpenMPTesting.cmake
===================================================================
--- openmp/cmake/OpenMPTesting.cmake
+++ openmp/cmake/OpenMPTesting.cmake
@@ -34,6 +34,17 @@
     set(ENABLE_CHECK_TARGETS FALSE PARENT_SCOPE)
     return()
   endif()
+
+  find_program(OPENMP_NOT_EXECUTABLE
+    NAMES not
+    PATHS ${OPENMP_LLVM_TOOLS_DIR})
+  if (NOT OPENMP_NOT_EXECUTABLE)
+    message(STATUS "Cannot find 'not'.")
+    message(STATUS "Please put 'not' in your PATH, set OPENMP_NOT_EXECUTABLE to its full path, or point OPENMP_LLVM_TOOLS_DIR to its directory.")
+    message(WARNING "The check targets will not be available!")
+    set(ENABLE_CHECK_TARGETS FALSE PARENT_SCOPE)
+    return()
+  endif()
 endfunction()
 
 if (${OPENMP_STANDALONE_BUILD})
@@ -55,6 +66,7 @@
   separate_arguments(OPENMP_LIT_ARGS)
 else()
   set(OPENMP_FILECHECK_EXECUTABLE ${LLVM_RUNTIME_OUTPUT_INTDIR}/FileCheck)
+  set(OPENMP_NOT_EXECUTABLE ${LLVM_RUNTIME_OUTPUT_INTDIR}/not)
 endif()
 
 # Macro to extract information about compiler from file. (no own scope)
Index: openmp/libomptarget/src/omptarget.cpp
===================================================================
--- openmp/libomptarget/src/omptarget.cpp
+++ openmp/libomptarget/src/omptarget.cpp
@@ -286,6 +286,7 @@
       // NULL, so getOrAlloc() returning NULL is not an error.
       DP("Call to getOrAllocTgtPtr returned null pointer (device failure or "
           "illegal mapping).\n");
+      return OFFLOAD_FAIL;
     }
     DP("There are %" PRId64 " bytes allocated at target address " DPxMOD
         " - is%s new\n", data_size, DPxPTR(TgtPtrBegin),
Index: openmp/libomptarget/test/lit.cfg
===================================================================
--- openmp/libomptarget/test/lit.cfg
+++ openmp/libomptarget/test/lit.cfg
@@ -101,6 +101,9 @@
         config.substitutions.append(("%libomptarget-run-" + \
             libomptarget_target, \
             "%t-" + libomptarget_target))
+        config.substitutions.append(("%libomptarget-run-fail-" + \
+            libomptarget_target, \
+            config.libomptarget_not + " %t-" + libomptarget_target))
         config.substitutions.append(("%clangxx-" + libomptarget_target, \
             "%clangxx %openmp_flags %flags -fopenmp-targets=" + libomptarget_target))
         config.substitutions.append(("%clang-" + libomptarget_target, \
@@ -129,6 +132,9 @@
         config.substitutions.append(("%libomptarget-run-" + \
             libomptarget_target, \
             "echo ignored-command"))
+        config.substitutions.append(("%libomptarget-run-fail-" + \
+            libomptarget_target, \
+            "echo ignored-command"))
         config.substitutions.append(("%clang-" + libomptarget_target, \
             "echo ignored-command"))
         config.substitutions.append(("%clangxx-" + libomptarget_target, \
Index: openmp/libomptarget/test/lit.site.cfg.in
===================================================================
--- openmp/libomptarget/test/lit.site.cfg.in
+++ openmp/libomptarget/test/lit.site.cfg.in
@@ -13,6 +13,7 @@
 config.libomptarget_all_targets = "@LIBOMPTARGET_ALL_TARGETS@".split()
 config.libomptarget_system_targets = "@LIBOMPTARGET_SYSTEM_TARGETS@".split()
 config.libomptarget_filecheck = "@OPENMP_FILECHECK_EXECUTABLE@"
+config.libomptarget_not = "@OPENMP_NOT_EXECUTABLE@"
 config.libomptarget_debug = @LIBOMPTARGET_DEBUG@
 
 # Let the main config do the real work.
Index: openmp/libomptarget/test/mapping/alloc_fail.c
===================================================================
--- /dev/null
+++ openmp/libomptarget/test/mapping/alloc_fail.c
@@ -0,0 +1,25 @@
+// RUN: %libomptarget-compile-aarch64-unknown-linux-gnu
+// RUN: %libomptarget-run-fail-aarch64-unknown-linux-gnu 2>&1 \
+// RUN: | %fcheck-aarch64-unknown-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64-ibm-linux-gnu
+// RUN: %libomptarget-run-fail-powerpc64-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64le-ibm-linux-gnu
+// RUN: %libomptarget-run-fail-powerpc64le-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64le-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-x86_64-pc-linux-gnu
+// RUN: %libomptarget-run-fail-x86_64-pc-linux-gnu 2>&1 \
+// RUN: | %fcheck-x86_64-pc-linux-gnu
+
+// CHECK: Libomptarget fatal error 1: failure of target construct while offloading is mandatory
+
+int main() {
+  int arr[4] = {0, 1, 2, 3};
+#pragma omp target data map(alloc: arr[0:2])
+#pragma omp target data map(alloc: arr[1:2])
+  ;
+  return 0;
+}