diff --git a/llvm/utils/lit/tests/Inputs/shtest-output-printing/basic.txt b/llvm/utils/lit/tests/Inputs/shtest-output-printing/basic.txt
index 4899c7e63db4..fb3a3e000789 100644
--- a/llvm/utils/lit/tests/Inputs/shtest-output-printing/basic.txt
+++ b/llvm/utils/lit/tests/Inputs/shtest-output-printing/basic.txt
@@ -1,3 +1,3 @@
 # RUN: true
 # RUN: echo hi
-# RUN: wc missing-file &> %t.out
+# RUN: not not wc missing-file &> %t.out
diff --git a/llvm/utils/lit/tests/shtest-format.py b/llvm/utils/lit/tests/shtest-format.py
index 8c318697195a..0031ccf711b6 100644
--- a/llvm/utils/lit/tests/shtest-format.py
+++ b/llvm/utils/lit/tests/shtest-format.py
@@ -1,170 +1,170 @@
 # Check the various features of the ShTest format.
 #
 # RUN: rm -f %t.xml
 # RUN: not %{lit} -j 1 -v %{inputs}/shtest-format --xunit-xml-output %t.xml > %t.out
 # RUN: FileCheck < %t.out %s
 # RUN: FileCheck --check-prefix=XUNIT < %t.xml %s
 
 # END.
 
 # CHECK: -- Testing:
 
 # CHECK: PASS: shtest-format :: argv0.txt
 # CHECK: FAIL: shtest-format :: external_shell/fail.txt
 # CHECK-NEXT: *** TEST 'shtest-format :: external_shell/fail.txt' FAILED ***
 # CHECK: Command Output (stdout):
 # CHECK-NEXT: --
 # CHECK-NEXT: line 1: failed test output on stdout
 # CHECK-NEXT: line 2: failed test output on stdout
 # CHECK: Command Output (stderr):
 # CHECK-NEXT: --
-# CHECK-NEXT: cat{{(\.exe)?}}: does-not-exist: No such file or directory
+# CHECK-NEXT: cat{{(\.exe)?}}: {{cannot open does-not-exist|does-not-exist: No such file or directory}}
 # CHECK: --
 
 # CHECK: FAIL: shtest-format :: external_shell/fail_with_bad_encoding.txt
 # CHECK-NEXT: *** TEST 'shtest-format :: external_shell/fail_with_bad_encoding.txt' FAILED ***
 # CHECK: Command Output (stdout):
 # CHECK-NEXT: --
 # CHECK-NEXT: a line with bad encoding:
 # CHECK: --
 
 # CHECK: PASS: shtest-format :: external_shell/pass.txt
 
 # CHECK: FAIL: shtest-format :: fail.txt
 # CHECK-NEXT: *** TEST 'shtest-format :: fail.txt' FAILED ***
 # CHECK-NEXT: Script:
 # CHECK-NEXT: --
 # CHECK-NEXT: printf "line 1
 # CHECK-NEXT: false
 # CHECK-NEXT: --
 # CHECK-NEXT: Exit Code: 1
 #
 # CHECK: Command Output (stdout):
 # CHECK-NEXT: --
 # CHECK-NEXT: $ ":" "RUN: at line 1"
 # CHECK-NEXT: $ "printf"
 # CHECK-NEXT: # command output:
 # CHECK-NEXT: line 1: failed test output on stdout
 # CHECK-NEXT: line 2: failed test output on stdout
 
 # CHECK: UNRESOLVED: shtest-format :: no-test-line.txt
 # CHECK: PASS: shtest-format :: pass.txt
 # CHECK: UNSUPPORTED: shtest-format :: requires-any-missing.txt
 # CHECK: PASS: shtest-format :: requires-any-present.txt
 # CHECK: UNSUPPORTED: shtest-format :: requires-missing.txt
 # CHECK: PASS: shtest-format :: requires-present.txt
 # CHECK: UNRESOLVED: shtest-format :: requires-star.txt
 # CHECK: UNSUPPORTED: shtest-format :: requires-triple.txt
 # CHECK: PASS: shtest-format :: unsupported-expr-false.txt
 # CHECK: UNSUPPORTED: shtest-format :: unsupported-expr-true.txt
 # CHECK: UNRESOLVED: shtest-format :: unsupported-star.txt
 # CHECK: UNSUPPORTED: shtest-format :: unsupported_dir/some-test.txt
 # CHECK: PASS: shtest-format :: xfail-expr-false.txt
 # CHECK: XFAIL: shtest-format :: xfail-expr-true.txt
 # CHECK: XFAIL: shtest-format :: xfail-feature.txt
 # CHECK: XFAIL: shtest-format :: xfail-target.txt
 # CHECK: XFAIL: shtest-format :: xfail.txt
 # CHECK: XPASS: shtest-format :: xpass.txt
 # CHECK-NEXT: *** TEST 'shtest-format :: xpass.txt' FAILED ***
 # CHECK-NEXT: Script
 # CHECK-NEXT: --
 # CHECK-NEXT: true
 # CHECK-NEXT: --
 # CHECK: Testing Time
 
 # CHECK: Unexpected Passing Tests (1)
 # CHECK: shtest-format :: xpass.txt
 
 # CHECK: Failing Tests (3)
 # CHECK: shtest-format :: external_shell/fail.txt
 # CHECK: shtest-format :: external_shell/fail_with_bad_encoding.txt
 # CHECK: shtest-format :: fail.txt
 
 # CHECK: Expected Passes    : 7
 # CHECK: Expected Failures  : 4
 # CHECK: Unsupported Tests  : 5
 # CHECK: Unresolved Tests   : 3
 # CHECK: Unexpected Passes  : 1
 # CHECK: Unexpected Failures: 3
 
 
 # XUNIT: <?xml version="1.0" encoding="UTF-8" ?>
 # XUNIT-NEXT: <testsuites>
 # XUNIT-NEXT: <testsuite name="shtest-format" tests="23" failures="7" skipped="5">
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="argv0.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.external_shell" name="fail.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 
 # XUNIT: <testcase classname="shtest-format.external_shell" name="fail_with_bad_encoding.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 # XUNIT: <testcase classname="shtest-format.external_shell" name="pass.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="fail.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="no-test-line.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="pass.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-any-missing.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT:<skipped message="Skipping because of: a-missing-feature || a-missing-feature-2" />
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-any-present.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-missing.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT:<skipped message="Skipping because of: a-missing-feature" />
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-present.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-star.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="requires-triple.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT:<skipped message="Skipping because of: x86_64" />
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="unsupported-expr-false.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="unsupported-expr-true.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT:<skipped message="Skipping because of configuration." />
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="unsupported-star.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 # XUNIT: <testcase classname="shtest-format.unsupported_dir" name="some-test.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT:<skipped message="Skipping because of configuration." />
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xfail-expr-false.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xfail-expr-true.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xfail-feature.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xfail-target.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xfail.txt" time="{{[0-9]+\.[0-9]+}}"/>
 
 # XUNIT: <testcase classname="shtest-format.shtest-format" name="xpass.txt" time="{{[0-9]+\.[0-9]+}}">
 # XUNIT-NEXT: <failure{{[ ]*}}>
 # XUNIT: </failure>
 # XUNIT-NEXT: </testcase>
 
 # XUNIT: </testsuite>
 # XUNIT-NEXT: </testsuites>
diff --git a/llvm/utils/lit/tests/shtest-output-printing.py b/llvm/utils/lit/tests/shtest-output-printing.py
index 2344ef200367..80304258fd95 100644
--- a/llvm/utils/lit/tests/shtest-output-printing.py
+++ b/llvm/utils/lit/tests/shtest-output-printing.py
@@ -1,31 +1,31 @@
 # Check the various features of the ShTest format.
 #
 # RUN: not %{lit} -j 1 -v %{inputs}/shtest-output-printing > %t.out
 # RUN: FileCheck --input-file %t.out %s
 #
 # END.
 
 # CHECK: -- Testing:
 
 # CHECK: FAIL: shtest-output-printing :: basic.txt
 # CHECK-NEXT: *** TEST 'shtest-output-printing :: basic.txt' FAILED ***
 # CHECK-NEXT: Script:
 # CHECK-NEXT: --
 # CHECK:      --
 # CHECK-NEXT: Exit Code: 1
 #
 # CHECK:      Command Output
 # CHECK-NEXT: --
 # CHECK-NEXT: $ ":" "RUN: at line 1"
 # CHECK-NEXT: $ "true"
 # CHECK-NEXT: $ ":" "RUN: at line 2"
 # CHECK-NEXT: $ "echo" "hi"
 # CHECK-NEXT: # command output:
 # CHECK-NEXT: hi
 #
 # CHECK:      $ ":" "RUN: at line 3"
-# CHECK-NEXT: $ "wc" "missing-file"
+# CHECK-NEXT: $ "not" "not" "wc" "missing-file"
 # CHECK-NEXT: # redirected output from '{{.*(/|\\\\)}}basic.txt.tmp.out':
-# CHECK-NEXT: missing-file{{.*}} No such file or directory
+# CHECK-NEXT: {{cannot open missing-file|missing-file.* No such file or directory}}
 # CHECK:      note: command had no output on stdout or stderr
 # CHECK-NEXT: error: command failed with exit status: 1