diff --git a/llvm/test/CMakeLists.txt b/llvm/test/CMakeLists.txt
--- a/llvm/test/CMakeLists.txt
+++ b/llvm/test/CMakeLists.txt
@@ -162,6 +162,15 @@
 add_custom_target(llvm-test-depends DEPENDS ${LLVM_TEST_DEPENDS})
 set_target_properties(llvm-test-depends PROPERTIES FOLDER "Tests")
 
+# Inform people that check-llvm should be run with Release builds.
+if(NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "RELEASE")
+  add_custom_target(check-llvm-inform
+    COMMAND ${CMAKE_COMMAND} -E cmake_echo_color --red "Running check-llvm will be slow, use a Release build for performance"
+    USES_TERMINAL
+    )
+  set(LLVM_TEST_DEPENDS check-llvm-inform ${LLVM_TEST_DEPENDS})
+endif()
+
 add_lit_testsuite(check-llvm "Running the LLVM regression tests"
   ${CMAKE_CURRENT_BINARY_DIR}
   DEPENDS ${LLVM_TEST_DEPENDS}
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/archive.test b/llvm/test/tools/llvm-dwarfdump/X86/archive.test
--- a/llvm/test/tools/llvm-dwarfdump/X86/archive.test
+++ b/llvm/test/tools/llvm-dwarfdump/X86/archive.test
@@ -11,6 +11,12 @@
 I386: file format Mach-O 32-bit i386
 I386-NOT: 64-bit
 
+RUN: llvm-dwarfdump --debug-info %S/../../dsymutil/Inputs/libfat-test.a \
+RUN:   --arch=i686 | FileCheck %s --check-prefix=I686
+I686-NOT: 64-bit
+I686: file format Mach-O 32-bit i386
+I686-NOT: 64-bit
+
 RUN: llvm-dwarfdump --debug-info %S/../../dsymutil/Inputs/libfat-test.a \
 RUN:   --arch=i386 --arch=x86_64 | FileCheck %s
 
diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -258,12 +258,11 @@
     return true;
 
   if (auto *MachO = dyn_cast<MachOObjectFile>(&Obj)) {
-    std::string ObjArch =
-        Triple::getArchTypeName(MachO->getArchTriple().getArch());
+    auto ObjArch = MachO->getArchTriple().getArch();
 
     for (auto Arch : ArchFilters) {
       // Match name.
-      if (Arch == ObjArch)
+      if (Triple(Arch).getArch() == ObjArch)
         return true;
 
       // Match architecture number.