diff --git a/llvm/unittests/ExecutionEngine/Orc/OrcCAPITest.cpp b/llvm/unittests/ExecutionEngine/Orc/OrcCAPITest.cpp
--- a/llvm/unittests/ExecutionEngine/Orc/OrcCAPITest.cpp
+++ b/llvm/unittests/ExecutionEngine/Orc/OrcCAPITest.cpp
@@ -17,6 +17,17 @@
 
 using namespace llvm;
 
+// Writing 64-bit XCOFF isn't supported yet, so we expect some tests to crash.
+#if defined(_AIX) && defined(__64BIT__)
+#define EXPECT_DEATH_ON_AIX_64BIT_THEN_SKIP(...)                               \
+  do {                                                                         \
+    EXPECT_DEATH(__VA_ARGS__);                                                 \
+    return;                                                                    \
+  } while (false)
+#else
+#define EXPECT_DEATH_ON_AIX_64BIT_THEN_SKIP(statement, regex) (statement)
+#endif
+
 // OrcCAPITestBase contains several helper methods and pointers for unit tests
 // written for the LLVM-C API. It provides the following helpers:
 //
@@ -266,9 +277,15 @@
     FAIL() << "Failed to add LLVM IR module to LLJIT (triple = " << TargetTriple
            << "): " << toString(E);
   LLVMOrcJITTargetAddress TestFnAddr;
-  if (LLVMErrorRef E = LLVMOrcLLJITLookup(Jit, &TestFnAddr, "sum"))
-    FAIL() << "Symbol \"sum\" was not added into JIT (triple = " << TargetTriple
-           << "): " << toString(E);
+  {
+    LLVMErrorRef E = nullptr;
+    EXPECT_DEATH_ON_AIX_64BIT_THEN_SKIP(
+        E = LLVMOrcLLJITLookup(Jit, &TestFnAddr, "sum"),
+        "64-bit XCOFF object files are not supported yet");
+    if (E)
+      FAIL() << "Symbol \"sum\" was not added into JIT (triple = "
+             << TargetTriple << "): " << toString(E);
+  }
   ASSERT_TRUE(!!TestFnAddr);
   LLVMOrcResourceTrackerRemove(RT);
   LLVMOrcJITTargetAddress OutAddr;
@@ -295,9 +312,15 @@
     FAIL() << "Failed to add LLVM IR module to LLJIT (triple = " << TargetTriple
            << "): " << toString(E);
   LLVMOrcJITTargetAddress Addr;
-  if (LLVMErrorRef E = LLVMOrcLLJITLookup(Jit, &Addr, "sum"))
-    FAIL() << "Symbol \"sum\" was not added into JIT (triple = " << TargetTriple
-           << "): " << toString(E);
+  {
+    LLVMErrorRef E = nullptr;
+    EXPECT_DEATH_ON_AIX_64BIT_THEN_SKIP(
+        E = LLVMOrcLLJITLookup(Jit, &Addr, "sum"),
+        "64-bit XCOFF object files are not supported yet");
+    if (E)
+      FAIL() << "Symbol \"sum\" was not added into JIT (triple = "
+             << TargetTriple << "): " << toString(E);
+  }
   LLVMOrcResourceTrackerTransferTo(DefaultRT, RT2);
   LLVMErrorRef Err = LLVMOrcLLJITLookup(Jit, &Addr, "sum");
   ASSERT_FALSE(Err);
@@ -319,9 +342,15 @@
     FAIL() << "Failed to add LLVM IR module to LLJIT (triple = " << TargetTriple
            << ")" << toString(E);
   LLVMOrcJITTargetAddress TestFnAddr;
-  if (LLVMErrorRef E = LLVMOrcLLJITLookup(Jit, &TestFnAddr, "sum"))
-    FAIL() << "Symbol \"sum\" was not added into JIT (triple = " << TargetTriple
-           << "): " << toString(E);
+  {
+    LLVMErrorRef E = nullptr;
+    EXPECT_DEATH_ON_AIX_64BIT_THEN_SKIP(
+        E = LLVMOrcLLJITLookup(Jit, &TestFnAddr, "sum"),
+        "64-bit XCOFF object files are not supported yet");
+    if (E)
+      FAIL() << "Symbol \"sum\" was not added into JIT (triple = "
+             << TargetTriple << "): " << toString(E);
+  }
   auto *SumFn = (SumFunctionType)(TestFnAddr);
   int32_t Result = SumFn(1, 1);
   ASSERT_EQ(2, Result);