diff --git a/llvm/test/tools/llvm-mc/fatal_warnings.test b/llvm/test/tools/llvm-mc/fatal_warnings.test
--- a/llvm/test/tools/llvm-mc/fatal_warnings.test
+++ b/llvm/test/tools/llvm-mc/fatal_warnings.test
@@ -1,4 +1,5 @@
 # RUN: not llvm-mc --fatal-warnings %s 2>&1 | FileCheck %s
+# XFAIL: xcore
 
 # CHECK: error: .warning directive invoked in source file
 .warning
diff --git a/llvm/test/tools/llvm-mc/no_warnings.test b/llvm/test/tools/llvm-mc/no_warnings.test
--- a/llvm/test/tools/llvm-mc/no_warnings.test
+++ b/llvm/test/tools/llvm-mc/no_warnings.test
@@ -1,4 +1,5 @@
 # RUN: llvm-mc --no-warn %s 2>&1 | FileCheck %s
+# XFAIL: xcore
 
 # CHECK-NOT: warning:
 .warning