[ELF] Use shell to check the file permissions

[phosek]

Summary

This is less error-prone to mask settings than stat.

[ruiu]

LGTM

I believe it's still fragile against weird umask setting (such as 444), but that's in practice not an issue.

Don't you need to run this only on Unix?

[ruiu]

I wonder if replacing gnustat with shell and use [ -x <filename> ] is more robust than using gnustat. At least there's a precedence in clang/test/Driver/target-override.c.

[phosek]

Done

[ruiu]

LGTM

test/ELF/file-access.s

1

"shell" means basically "non-Windows", so I don't think you need "linux". This test should work fine on any Unix or on macOS.

5–6

I think you can remove FileCheck and just do

RUN: [ ! -x %t1.o ]

because lit checks its subprocesses exit codes.

7

Likewise, just

RUN: [ -x %t2.so ]

test/ELF/file-access.s

-# REQUIRES: x86, gnustat
+# REQUIRES: x86, shell
 
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
 # RUN: ld.lld -r %t.o -o %t1.o
-# RUN: stat -c %%A %t1.o | FileCheck --check-prefix=CHECK-RELOC %s
-# CHECK-RELOC: -rw-r--r--
+# RUN: [ ! -x %t1.o ]
 # RUN: ld.lld -shared %t.o -o %t2.so
-# RUN: stat -c %%A %t2.so | FileCheck --check-prefix=CHECK-SHARED %s
-# CHECK-SHARED: -rwxr-xr-x
+# RUN: [ -x %t2.so ]
 # RUN: ld.lld %t.o -o %t3
-# RUN: stat -c %%A %t3 | FileCheck --check-prefix=CHECK-EXEC %s
-# CHECK-EXEC: -rwxr-xr-x
+# RUN: [ -x %t3 ]
 
 .global _start
 _start:
   nop

test/lit.cfg.py

 
 tar_executable = lit.util.which('tar', config.environment['PATH'])
 if tar_executable:
     tar_version = subprocess.Popen(
         [tar_executable, '--version'], stdout=subprocess.PIPE, env={'LANG': 'C'})
     if 'GNU tar' in tar_version.stdout.read().decode():
         config.available_features.add('gnutar')
     tar_version.wait()
-
-stat_executable = lit.util.which('stat', config.environment['PATH'])
-if stat_executable:
-    stat_version = subprocess.Popen(
-        [stat_executable, '--version'], stdout=subprocess.PIPE, env={'LANG': 'C'})
-    if 'GNU coreutils' in stat_version.stdout.read().decode():
-        config.available_features.add('gnustat')
-    stat_version.wait()