diff --git a/test/MC/AArch64/ldr-pseudo-obj-errors.s b/test/MC/AArch64/ldr-pseudo-obj-errors.s
index d851917b714..b486abe27e3 100644
--- a/test/MC/AArch64/ldr-pseudo-obj-errors.s
+++ b/test/MC/AArch64/ldr-pseudo-obj-errors.s
@@ -1,4 +1,4 @@
-//RUN: not llvm-mc -triple=aarch64-linux -filetype=obj %s -o %t1 2> %t2
+//RUN: not llvm-mc -triple=aarch64-linux -filetype=obj %s -o /dev/null 2> %t2
 //RUN: cat %t2 | FileCheck %s
 
 //These tests look for errors that should be reported for invalid object layout
diff --git a/test/MC/ELF/dwo-restrict-relocs.s b/test/MC/ELF/dwo-restrict-relocs.s
index b624d40aad7..1bc15101b23 100644
--- a/test/MC/ELF/dwo-restrict-relocs.s
+++ b/test/MC/ELF/dwo-restrict-relocs.s
@@ -1,4 +1,4 @@
-// RUN: not llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o %t1 -split-dwarf-file %t2 2>&1 | FileCheck %s
+// RUN: not llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o /dev/null -split-dwarf-file %t2 2>&1 | FileCheck %s
 
 // CHECK: error: A relocation may not refer to a dwo section
 .quad .foo.dwo
diff --git a/test/tools/dsymutil/ARM/fat-arch-name.test b/test/tools/dsymutil/ARM/fat-arch-name.test
index 14d33d0adcb..be12affba5b 100644
--- a/test/tools/dsymutil/ARM/fat-arch-name.test
+++ b/test/tools/dsymutil/ARM/fat-arch-name.test
@@ -1,5 +1,5 @@
 # REQUIRES: object-emission
-# RUN: dsymutil -no-output %p/../Inputs/fat-test.arm.dylib -o %t.dSYM -verbose 2>&1 | FileCheck %s
+# RUN: dsymutil -no-output %p/../Inputs/fat-test.arm.dylib -o /dev/null -verbose 2>&1 | FileCheck %s
 
 # We detect thumb triples from the binaries, because those are the only ones
 # that are guaranteed to be able to generate a Target instance (for example
diff --git a/test/tools/dsymutil/ARM/fat-threading.test b/test/tools/dsymutil/ARM/fat-threading.test
index a72381291ef..850979af71a 100644
--- a/test/tools/dsymutil/ARM/fat-threading.test
+++ b/test/tools/dsymutil/ARM/fat-threading.test
@@ -1,4 +1,4 @@
 # REQUIRES: object-emission
 # By default, dsymutil spawns one thread per architecture and this test just
 # ensures that things don't break when processing multiple archs.
-# RUN: dsymutil -no-output %p/../Inputs/fat-test.arm.dylib -o %t.brief.dSYM 2>&1
+# RUN: dsymutil -no-output %p/../Inputs/fat-test.arm.dylib -o /dev/null 2>&1
diff --git a/test/tools/llvm-mc/basic.test b/test/tools/llvm-mc/basic.test
index edac65257e5..c7480dc6a87 100644
--- a/test/tools/llvm-mc/basic.test
+++ b/test/tools/llvm-mc/basic.test
@@ -1,3 +1,3 @@
-# RUN: not llvm-mc %t.blah -o %t2 2>&1 | FileCheck --check-prefix=ENOENT %s
+# RUN: not llvm-mc %t.blah -o /dev/null 2>&1 | FileCheck --check-prefix=ENOENT %s
 
 # ENOENT: {{.*}}.blah: {{[Nn]}}o such file or directory
diff --git a/test/tools/llvm-mca/X86/in-order-cpu.s b/test/tools/llvm-mca/X86/in-order-cpu.s
index 7c58b3d83ba..483a4e24523 100644
--- a/test/tools/llvm-mca/X86/in-order-cpu.s
+++ b/test/tools/llvm-mca/X86/in-order-cpu.s
@@ -1,3 +1,3 @@
-# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=atom -o %t1 2>&1 | FileCheck %s
+# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=atom -o /dev/null 2>&1 | FileCheck %s
 
 # CHECK: error: please specify an out-of-order cpu. 'atom' is an in-order cpu.
diff --git a/test/tools/llvm-mca/X86/invalid-cpu.s b/test/tools/llvm-mca/X86/invalid-cpu.s
index 4298e7111e2..7457f8cac7e 100644
--- a/test/tools/llvm-mca/X86/invalid-cpu.s
+++ b/test/tools/llvm-mca/X86/invalid-cpu.s
@@ -1,3 +1,3 @@
-# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=foo -o %t1 2>&1 | FileCheck %s
+# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=foo -o /dev/null 2>&1 | FileCheck %s
 
 # CHECK: 'foo' is not a recognized processor for this target (ignoring processor)
diff --git a/test/tools/llvm-mca/X86/invalid-empty-file.s b/test/tools/llvm-mca/X86/invalid-empty-file.s
index 46b12d4defd..c727d7ceaed 100644
--- a/test/tools/llvm-mca/X86/invalid-empty-file.s
+++ b/test/tools/llvm-mca/X86/invalid-empty-file.s
@@ -1,3 +1,3 @@
-# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=btver2 -o %t1 2>&1 | FileCheck %s
+# RUN: not llvm-mca %s -mtriple=x86_64-unknown-unknown -mcpu=btver2 -o /dev/null 2>&1 | FileCheck %s
 
 # CHECK: error: no assembly instructions found.
diff --git a/test/tools/llvm-mca/invalid_input_file_name.test b/test/tools/llvm-mca/invalid_input_file_name.test
index 2d2d30af314..27fa972f29a 100644
--- a/test/tools/llvm-mca/invalid_input_file_name.test
+++ b/test/tools/llvm-mca/invalid_input_file_name.test
@@ -1,3 +1,3 @@
-# RUN: not llvm-mca %t.blah -o %t2 2>&1 | FileCheck --check-prefix=ENOENT %s
+# RUN: not llvm-mca %t.blah -o /dev/null 2>&1 | FileCheck --check-prefix=ENOENT %s
 
 # ENOENT: {{.*}}.blah: {{[Nn]}}o such file or directory