[MC] Rewrite stdin.s to use python

llvm/test/MC/COFF/stdin.py

@@ -0,0 +1,30 @@
+# RUN: echo "// comment" > %t.input
+# RUN: which llvm-mc | %python %s %t.input %t
+
+import argparse
+import subprocess
+import sys
+
+parser = argparse.ArgumentParser()
+parser.add_argument("input_file")
+parser.add_argument("temp_file")
+arguments = parser.parse_args()
+
+llvm_mc_binary = sys.stdin.readlines()[0].strip()
+
+with open(arguments.temp_file, "w") as mc_stdout:
+    ## We need to test that starting on an input stream with a non-zero offset
+    ## does not trigger an assertion in WinCOFFObjectWriter.cpp, so we seek
+    ## past zero for STDOUT.
+    mc_stdout.seek(4)
+    subprocess.run(
+        [
+            llvm_mc_binary,
+            "-filetype=obj",
+            "-triple",
+            "i686-pc-win32",
+            arguments.input_file,
+        ],
+        stdout=mc_stdout,
+        check=True,
+    )

llvm/test/tools/not/disable-symbolization.test

@@ -1,8 +1,8 @@
 # When building on Windows under cmd.exe and GnuWin32, 'env' fails if no
 # arguments are provided.
 # UNSUPPORTED: system-windows
-# RUN: not --crash env > %t || true
-# RUN: cmp -s %t /dev/null || FileCheck %s < %t
+# RUN: not --crash bash -c env > %t || true
+# RUN: FileCheck %s < %t
 
 # CHECK-DAG: LLVM_DISABLE_CRASH_REPORT=1
 # CHECK-DAG: LLVM_DISABLE_SYMBOLIZATION=1