[test-release] fallback to py3's venv module

If virtualenv is not available, we can look for py3's venv instead. We only
use this particular env for installing and running the test suite.

diff --git a/llvm/utils/release/test-release.sh b/llvm/utils/release/test-release.sh
index 5351ae1064f9eb51c8c8734a6892b0a52adbbfe9..6bb6f42b080589209813a36754843096f1cec784 100755 (executable)
--- a/llvm/utils/release/test-release.sh
+++ b/llvm/utils/release/test-release.sh
@@ -502,12 +502,18 @@ fi
 # Setup the test-suite.  Do this early so we can catch failures before
 # we do the full 3 stage build.
 if [ $do_test_suite = "yes" ]; then
+  venv=virtualenv
+  if ! type -P 'virtualenv' > /dev/null 2>&1 ; then
+    check_program_exists 'python3'
+    venv="python3 -m venv"
+  fi
+
   SandboxDir="$BuildDir/sandbox"
   Lit=$SandboxDir/bin/lit
   TestSuiteBuildDir="$BuildDir/test-suite-build"
   TestSuiteSrcDir="$BuildDir/llvm-test-suite"
 
-  virtualenv $SandboxDir
+  ${venv} $SandboxDir
   $SandboxDir/bin/python $BuildDir/llvm-project/llvm/utils/lit/setup.py install
   mkdir -p $TestSuiteBuildDir
 fi